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| DE8681 CML Microcircuits COMMUNICATION SEMICONDUCTORS UM8681/3 January 2004 V.22bis User Manual for a "socket modem" Provisional Issue 1.0 Features * PC Controlled via Terminal Emulator * FCC68 or CTR21 DAA * Single 3V or 5V dc power supply operation * Break-off PCB sections * Supplied with PCB layout data * CMX868-based socket modem Reference Design * Fully Isolated 2-Wire Line Interface * Opto Isolated Ring Detect Circuitry and OptoMOS Hook Relay * `AT' Command Compatible Firmware * On-board FLASH PIC Microcontroller 1.1 Brief Description The DE8681 Demonstration Board is a reference design for the CMX868 V.22 bis modem IC. On the main "socket modem" section it also contains the line interface components and a Flash PIC C. Attached to the main section are two break-off sections which contain a 9-pin D type socket for PC serial communications, a Flash PIC programming connector, an RJ11 line connector and various LEDs for indicating signal activity. AT Commands are used to control the demonstration board via a standard terminal emulator program running on a host PC. Interfacing to the Demonstration Board can be via socket pins on the socket modem section, or via the connectors provided on the break-off sections. The board can be operated at 3V or 5V dc, which must be provided by an external, regulated power supply. The PCB has been laid out for both CTR21 and FCC68 compliant DAA designs. However the components fitted are for the simplified FCC68 design. Instructions are given for users who wish to fit the CTR21 components. Hardware has been provided on the socket modem section for CLI Type 1, but a PIC firmware upgrade will be required to enable this function, which may be available at a later date. With this is mind, the socket modem has been provided with a Flash PIC Microcontroller that can be serially programmed in circuit via the RS232 connection. (c) 2004 CML Microsystems Plc 1 UM/8681/3 CMX868 Reference Design and Demonstration Board DE8681 CONTENTS Section 1.0 1.0 1.1 1.2 Page Features ............................................................................................... 1 Features ............................................................................................... 1 Brief Description.................................................................................. 1 Preliminary Information ...................................................................... 4 1.2.1 Equipment ............................................................................... 4 1.2.2 Handling Precautions ............................................................. 4 1.2.3 Approvals ................................................................................ 4 Quick Start ........................................................................................... 5 1.3.1 Setting-Up................................................................................ 5 1.3.2 Operation................................................................................. 5 Signal Lists .......................................................................................... 7 Circuit Schematics and Board Layout.............................................. 10 Detailed Description .......................................................................... 14 1.6.1 Hardware Description ........................................................... 14 1.6.2 Firmware Description............................................................ 15 1.6.4 Software Description ............................................................ 26 1.6.5 Additional Information.......................................................... 28 1.6.6 Example DE8681 Modem Tests ............................................ 30 1.6.7 Example DE8681 Device Evaluation Tests .......................... 31 1.6.8 Trouble Shooting .................................................................. 33 Performance Specification................................................................ 34 1.7.1 Electrical Performance.......................................................... 34 1.3 1.4 1.5 1.6 1.7 (c) 2004 CML Microsystems Plc 2 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 Modem or Telephone Line Simulator J3 J61 DE8681 J26/J41 Power Supply J4 RS232 Cable IBM-PC Figure 1 Block Diagram (c) 2004 CML Microsystems Plc 3 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 1.2 1.2.1 Preliminary Information Equipment The following equipment is needed to use this demonstration board: 1.2.1.1 3Vdc or 5Vdc Regulated Power Supply 1.2.1.2 A PC equipped with a serial port running a terminal emulation program such as Microsofts' Hyperterminal. 1.2.1.3 For PIC re-programming with the software supplied (PICPROGF.EXE), an IBM compatible PC, 66MHz `486 or better, running Microsoft WindowsTM 95,98 or DOS. The software runs most efficiently under DOS and cannot be used with Windows NT. 1.2.2 Handling Precautions 1.2.2.1 Static Protection This product uses low power CMOS circuits, which can be damaged by electrostatic discharge. Partially damaged circuits can function erroneously, leading to misleading results. Observe ESD precautions at all times when handling this product. 1.2.2.2 Contents - Unpacking Please ensure that you have received all of the items on the separate information sheet (EK8681) and notify CML within 7 working days if the delivery is incomplete. 1.2.3 Approvals This product is designed to meet CTR21/FCC68 telecom approval requirements. Users are advised to observe local statutory requirements which may apply to this product before direct or indirect connection to any public telecommunication system. (c) 2004 CML Microsystems Plc 4 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 1.3 Quick Start This section provides instructions for users who wish to experiment immediately with the demonstration board. A fuller description of the board and its use appears later in this document. 1.3.1 Setting-Up THE DE8681 COMES PRE-CONFIGURED AS A FCC68 MODEM, USING THE CMX868 TSSOP DEVICE AND A PRE-PROGRAMMED FLASH PIC C, FOR OPERATION AT 5.0 VOLTS. See section 1.6 for the alternative component values required for 3.0V or CTR21 operation. An RJ11 (US style) phone jack, J3, for 2-wire line connection is provided on one of the break-off board sections. Power is connected via socket pins 61(VDD) and 41(GND). See pinout, figure 2. Attach the 9-way RS232 cable between connector J4 and the serial port of the PC. Connect an external modem/line simulator to the evaluation kit using a suitable RJ11 telephone cable (not supplied). The DE8681 is supplied with the break-off sections of the board intact. If a socket modem using the industry standard footprint is required, detach these break-off sections from the Demonstration Board PCB by using a suitable tool to scribe along the perforations that join the break-off sections to the main PCB. Scribe on both top and bottom sides of the board and ensure that the scribed line completely cuts any copper tracks entering or leaving the break-off sections from the main PCB. When this is done, gently break-off the first section on which connector J4 (9-pin D Type socket) is mounted, then break-off the second section on which the RJ11 socket is mounted. All connections to the remaining socket modem must now be made through the PCB connector pins. 1.3.2 Operation The DE8681 demonstration board allows the user to perform calling, answering and simple data transfer with a suitable simulator or external third party modem (not supplied). The board is controlled by the AT command set described in Section 1.6.3, by running a terminal emulator program on the host PC. A suitable emulator is the `HyperTerminal' program, which operates under Windows 95/NT systems. The DE8681 AT command set consists of Basic, Extended and CML Specific commands. The board has two modes of operation: AT Command Mode In this mode the command processor firmware is constantly checking to see if the user has typed a valid AT command. When a valid command is received the firmware will execute that command. While the firmware is operating in this mode, the user can instruct it to manually answer a call, originate a call, go on/off hook, read/write to S-registers, issue CML specific AT commands, and perform any number of other AT command functions. The board always starts in AT Command mode after power is applied and board initialisation is complete. The CML specific AT commands allow the user to directly control the CMX868 device for evaluation purposes. Note, customer modified CMX868 device registers will be overwritten when Dial and Answer AT commands are executed. (c) 2004 CML Microsystems Plc 5 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 The Dial and Answer commands will execute the relevant DTMF transmit, call progress tone detection and negotiation (handshaking) firmware routines before a connection to a remote modem/simulator can be established. Negotiation may be aborted by pushing any key. Note, if the S0 register is modified to a non-zero value during this operating mode, the CMX868 status register will be polled every 20ms to check for ring detect status. If valid ringing is detected the DE8681 will automatically answer a call after n ring cycles, where n is equivalent to the contents of the S0 register. Data Transfer Mode After gaining a connection (i.e. successful negotiation) with a remote modem the board will be operating in data transfer mode. In this mode the board will transmit all the data it receives from the RS232 computer terminal to the remote modem via the 2-wire line. Likewise any data received from the remote modem via the 2-wire line will be sent to RS232 computer terminal. Whilst operating in this mode the data stream from the RS232 computer terminal is monitored for the escape code sequence (+++). If this sequence is encountered during data transfer the firmware will revert to on-line AT command mode. Whilst in on-line, AT command mode, the board to remote modem connection may be aborted by typing ATH0 (instructs modem to go onhook). Alternatively the user can enter relevant AT commands or return to data transfer mode by using the ATO command. The modem line speed is much lower than the speed of the RS232 interface (RS232 is running at 19200bps) and the DE8681 firmware only provides a small amount of data buffering. Therefore to prevent the data buffer from overflowing the data flow between the C and RS232 is controlled by the RTS/CTS (Request/Clear to Send) hardware handshake lines. The CMX868 settings used during negotiation and data transfer will be based on the contents of the S-registers when the call was originated or answered. The S-registers are described in Section 1.6.3. Certain S-register settings (relevant to the CMX868 configuration), modified during on-line AT command mode, will only take effect when a new call is originated or answered. For example, new CMX868 Tx gain settings (S25 register) modified in on-line AT command mode will be ignored until the next call. (c) 2004 CML Microsystems Plc 6 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 1.4 Signal Lists CONNECTOR PINOUT Connector Ref. J1 J2 J3 3 4 J4 1 2 3 4 5 6 7 8 9 J5 1 2 3 4 5 J24 J26 J29 J30 J31 J32 J33 J34 J35 J36 Connector Pin No. Signal Name TIP RING RING TIP DCD TXD RXD DTR VSS DSR RTS CTS RI /RESET /CTSTTL /RTSTTL VPP Vss /RESET VSS DCDIND RXDIND DTRIND TXDIND /RTSTTL /RXDTTL /TXDTTL /RITTL /DSRTTL /CTSTTL Signal Type Bi Bi Bi Bi Output Output Input Input Power Output Input Output Output Input Input Input Power Power Input Power Output Output Output Output Input Output Input Output Output Output Description Socket pin - Tip Socket pin - Ring RJ11 connector - Ring RJ11 connector - Tip 9-pin D Type connector - PC DCD 9-pin D Type connector - PC TXD 9-pin D Type connector - PC RXD 9-pin D Type connector - PC DTR 9-pin D Type connector - PC GND 9-pin D Type connector - PC DSR 9-pin D Type connector - PC RTS 9-pin D Type connector - PC CTS 9-pin D Type connector - PC RI 1 x 5 header - PIC reset 1 x 5 header - PIC programming data 1 x 5 header - PIC programming clock 1 x 5 header - PIC programming voltage 1 x 5 header Vss connection Socket pin - PIC reset VSS connection Socket pin - DCD LED indication Socket pin - RXD LED indication Socket pin - DTR LED indication Socket pin - TXD LED indication Socket pin - PIC RTS Socket pin - PIC TXD Socket pin - PIC RXD Socket pin - PIC RI Socket pin - PIC DSR Socket pin - PIC CTS J37 J38 (c) 2004 CML Microsystems Plc 7 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 CONNECTOR PINOUT Connector Ref. J39 J40 J41 J61 J63 Connector Pin No. Signal Name /DCDTTL /DTRTTL Vss VDD AVss Signal Type Output Input Power Power Power Description Socket pin - PIC DCD Socket pin - PIC DTR Vss connection +ve power from external power supply Analogue Vss connection - Not used LEDs LED Ref. D7 D8 D9 D10 D11 Description Illuminated when the line is in an off-hook state Illuminated when a carrier is detected at the remote modem end of the line Iluminated when the Socket Modem (DCE) is transmitting data to a host (DTE) Illuminated when the Socket Modem is receiving data from a host Illuminated when Data Terminal Ready is asserted by the host system. JUMPERS Jumper Ref. JP1 Positions 1-2 Default Position S/C Description Receiver enable (U8) Notes: Bi S/C = = Bidirectional Short Circuit (c) 2004 CML Microsystems Plc 8 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 TIP J1 RING J2 E1 C11 C12 J61 VDD T1 R13 C8 D1 R8 R6 R5 R9 R1 C10 D6 /RESET J24 GND J26 C24 C7 R7 R4 J41 GND J39 J38 J37 J36 J35 J34 J33 /DCDTTL /CTSTTL /DSRTTL /RITTL /TXDTTL /RXDTTL /RTSTTL X1 U2 C3 C5 C4 U1 DCDIND J29 RXDIND J30 DTRIND J31 TXDIND J32 C2 Figure 2, socket section pinout. Users with a revision B board, PCB024B, must note that the polarity for C11 shown on the silk screen is incorrect. Figures 2 and 5 of this document show corrected polarity. C6 C23 C1 C13 (c) 2004 CML Microsystems Plc 9 UM8681/3 1.5 CSN 11R5 1 2, 4 1 R11 3 U5 FZT605 R10 33k CDATA U4 3 + - 1 2 6 5 4 21 13 VSS VSS 17 VDD 16 TXA 15 14 VDD 24 IRQN 23 22 TXAN VBIAS REPDATA SERCLK 20 COMDATA 19 CSN 18 RXAN RXA 1 XTALN 2 XTAL/CLK 3 RLYDRV 4 VSS 5 RD 6 RT 7 VDD 8 VSS 9 RXAFB VSS 10 11 12 (c) 2004 CML Microsystems Plc BC846ALT1 C11 10uF (50V) R12 620R D5 AC AC SCLK VDD 2 RDATA IRQN OFFHOOK U6 ISOLATION BARRIER CBRHD-02 VDD C1 1 2 VDD D4 R8 33v (600W) 390R 2u2F C6 330nF R9 120k C9 100nF 2 CMX868 Reference Design and Demonstration Board C13 100nF C10 TIP F1 1.25A C12 330nF (250v) Break-off section 100nF R2 100k 6 5 4 R13 10k (0.5W) 1 3 E1 2 2 2 1 Circuit Schematics and Board Layout Figure 3a Modem Section with CTR21 Components 10 C23 100nF R7 180k C8 100nF 3 3 1 U1 CMX868E2 C24 220pF 4v3 4 1 2 D1 T1 D3 MIDCOM82107 3 RJ11SKT J3 18v SEC(Modem) PRI(Line) 1 D2 2 1 RING U3 C4 C7 R6 56k R5 1 COM EN 5 VDD GND 3 4 22pF 100pF R4 100k NO 2 ISOLATION BARRIER X1 MAX4501CUK-T U2 C2 5k6 C3 100nF C5 330nF 11M0592Hz 3 4 NECPS2701-1 22pF VDD VDD VDD R3 Break-off section VDD R16 D7 20k VDD R1 620R 470k Hook state indication OFFHOOK UM8681/3 DE8681 CSN nf 1 2 3 1 2, 4 R11 3 U5 nf R10 nf CDATA U4 nf SCLK C11 nf R12 620R + - 1 2 6 5 4 22 21 19 18 16 15 14 VSS VDD 24 VSS 17 CSN VDD TXA IRQN 23 TXAN SERCLK 20 VBIAS 13 REPDATA COMDATA XTALN XTAL/CLK RLYDRV VSS RD RT VDD VSS RXAFB RXAN RXA 1 2 3 4 5 6 7 8 9 VSS 10 11 12 (c) 2004 CML Microsystems Plc VDD D5 AC AC RDATA IRQN OFFHOOK U6 ISOLATION BARRIER nf VDD C1 1 2 VDD D4 R8 0R 390R 0R C6 330nF R9 120k C9 100nF 2 CMX868 Reference Design and Demonstration Board C13 100nF C10 TIP F1 1.25A C12 330nF (250v) Break-off section 100nF R2 100k 6 5 4 R13 10k (0.5W) 1 3 E1 2 2 2 1 Figure 3b Modem Section with FCC68 DAA Components (default) 11 C23 100nF R7 180k C8 33nF 3 U1 CMX868E2 C24 47pF 4v3 4 3 1 D1 T1 D3 1 RJ11SKT J3 MIDCOM82111 2 3 18v SEC(Modem) PRI(Line) 1 D2 2 1 RING U3 C4 C7 R6 62k R5 1 COM 4 NO EN 5 VDD GND 3 22pF 100pF R4 100k 2 ISOLATION BARRIER X1 MAX4501CUK-T U2 C2 5k6 C3 100nF C5 330nF 11M0592Hz 3 4 NECPS2701-1 22pF VDD VDD VDD R3 Break-off section VDD R16 D7 20k VDD R1 620R 470k Hook state indication OFFHOOK UM8681/3 DE8681 R22 /RESET 270R Break-off section 2 VPP /RESET R21 J5:A J5:B J5:C J5:D J5:E SW1 1 8 7 6 5 8 7 6 5 1 2 3 4 1 2 3 4 8 7 6 5 CMX868 Reference Design and Demonstration Board D8 C19 R17 DCDIND U7 28 27 1 /MCLR/Vpp 2 RA0/AN0 3 RA1/AN1 4 RA2/AN2 RB5 26 RB4 25 RB7 28 RB6 27 1 2 3 4 4 3 2 1 4 3 2 1 5 6 7 8 VDD TIP J32 J33 J34 J35 J36 RING /RESET DCDIND RXDIND DTRIND TXDIND /RTSTTL /RXDTTL /TXDTTL /RITTL 5 6 7 8 (c) 2004 CML Microsystems Plc Break-off section D12 100k VDD VDD /RTSTTL L1 C22 100uF (16V) C21 100nF 47uH 10k R14 /CTSTTL VDD RS2 1M VPP RS1 1M VDD RS5 1M D9 680R R18 680R RXDIND 26 25 24 23 22 /CTSTTL C18 100nF V+ /RTSTTL /DCDTTL C1+ 470nF U8 C2+ 1 C17 470nF VCC C1T1IN T2IN T3IN 21 20 19 18 17 R1OUT R2OUT T4IN R3OUT T5IN 16 R1OUTB 15 GND 2 C2- 3 D10 R19 680R 5 RA3/AN3/Vref 6 RA4/T0CKI 7 RA5//SS/AN4 8 VSS RB0/INT 9 OSC1/CLKIN RB1 22 21 RB3 24 RB2 23 TXDIND /DSRTTL C16 470nF DCD DSR CTS T3OUT 7 R1IN 8 V- 4 T1OUT 5 T2OUT 6 Figure 4 Control Section (common) 12 15pF 15pF 11 RC0/T1OSO/T1CKI RC1/T1OSC/CCP2 RC2/CCP1 RC3/SCK/SCL RC4/SDI/SDA 15 RC5/SDO 16 RC6/TX/CK 17 RC7/RX/DT 12 18 D11 J4 R20 680R DTRIND IRQN VDD C20 100nF DTR RTS R2IN 9 T4OUT 10 R3IN 11 T5OUT 12 /EN 13 14 C14 X2 OSC2/CLKOUT 1 2 3 4 5 6 7 8 9 C15 4MHz 10 VDD 20 VSS 19 RXD TXD RI 1 2 DB9F_CML CSN SCLK PIC16LF876SO 14 13 CDATA RDATA /TXDTTL /RXDTTL /RITTL /DTRTTL MBAUD /SHDN JP1 MAX3237CAI VDD R23 10k RS3 1M RS4 1M VDD /DSRTTL J37 /CTSTTL J38 /DCDTTL J39 /DTRTTL J40 J41 VDD J61 D6 6.2v (1W) J63 J1 J2 J24 J26 J29 J30 J31 UM8681/3 DE8681 CMX868 Reference Design and Demonstration Board DE8681 X1 C19 C11 T1 D6 C18 + U8 C22 R1 C12 R13 E1 D1 R8 C10 C8 R5 R9 R6 C5 U2 C4 U1 C3 C2 C13 R14 C17 C16 C1 C7 R7 C24 R4 C6 C23 1 SW1 J3 Board Mod 1234 R23 J5 R16 R17 R18 R20 R19 J4 R22 JP1 D7 D8 D9 D11 D10 HOOK DCD RXD DTR TXD F1 Figure 5 DE8681 top silk screen D12 C21 PIC16LF876SO R21 C14 L1 RS2 X2 RS1 RS5 R12 D4 U6 R11 U4 + D5 R10 C20 R2 RS4 R3 U3 D3 C9 U5 D2 C15 U7 RS3 Figure 6 DE8681 bottom silk screen (c) 2004 CML Microsystems Plc 13 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 1.6 1.6.1 Detailed Description Hardware Description 1.6.1.1 Operating Voltage The DE8681 can be operated at a VDD of 3 or 5Vdc (default), supplied by an external regulated power supply. Tables of component values for CTR21 and FCC68 DAAs are shown below: CTR21 DAA VDD 3.0 V 5.0 V R6 91K (93.5K) 56K (57.6K) R7 160K 180K C24 180pF 220pF R12 220R 620R D1 3.0V 4.3V FCC68 DAA VDD R6 R7 C24 3.0 V 100K (107K) 160K 39pF 5.0 V 62K (64.9K) 180K 47pF (The values shown in brackets are optimal values) 1.6.1.2 Clock/Oscillator R12 220R 620R D1 3.0V 4.3V The CMX868 is clocked at a frequency of 11.0592MHz, which is provided by crystal X1. The PIC C is clocked with a 4MHz crystal, X2. PIC microcontrollers programmed by CML are only configured for use with the on-board 4MHz crystal. 1.6.1.3 On-hook Caller ID This function provides a high impedance, on-hook AC path for the routing of Caller ID signals to the CMX868. Components C9, R5 and U2 provide this transmission path. C9 bypasses the optoMOS relay hook switch, allowing AC signals to pass through T1 when the Socket Modem is in an on-hook state. To compensate for losses incurred in the on-hook state, U2 and R5 increase the receive gain of the CMX868. 1.6.1.4 Simplified FCC68 Compliant DAA, as Shipped The values of R4, R6, R7, R8, R9, C8 and C24 are optimal values with respect to the Midcom 82111 transformer. Parts C10 and D4 are not required for this simplified design but are replaced with 0 links. 1.6.1.5 CTR21 Compliant DAA Components R10, R11, C11, D4, D5, U4 may be fitted to provide a 60mA current limit required by CTR21. Users with a revision B board, PCB024B, must note that the polarity for C11 shown on the silk screen is incorrect. Figures 2 and 5 of this document show corrected polarity. An alternative transformer, the Midcom 82107, must be fitted. Parts C10, C24, and R6 also have different values, to match the characteristics of the 82107 transformer and the CTR21 reference impedance. To be compliant with the CTR21 DTMF twist requirement, users must set S-register S28 bits 2-0 to 4. Please note that this will only be effective on DE8681 boards with a board mod state of 2 or higher, boards with a board mod state of 1 cannot meet the CTR21 DTMF twist requirement. (c) 2004 CML Microsystems Plc 14 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 1.6.1.6 Line Protection Line protection is provided by the Sidactor component E1. Sidactor is the trade name for a type of Transient Voltage Suppressor (TVS) manufactured by Teccor Electronics. 1.6.1.7 Ring Detection The ring detect threshold is approximately 20VRMS. 1.6.2 Firmware Description The PIC16LF876-04/SP C fitted on the DE8681 demonstration board has been programmed by CML before shipment with the latest version of firmware. Please read the separate information sheet (EK8681) and check the CML web site for firmware status. The latest source code and programming file (EF8681xx.HEX, where xx represents the version number) can be downloaded from the CML web site. The serial communications firmware supplied in the PIC C assumes the following configuration: 8 data bits, no parity, 1 stop bit and 19,200 baud with hardware flow control. The firmware routine run at start-up and reset performs the following important tasks: Peripheral Interrupt Initialisation C ports and I/O direction initialisation Serial Communication Interface (SCI) initialisation Serial Peripheral Interface (SPI) initialisation Loads factory profile 0 Resets CMX868 device. The message EF8681 Vx.x, will be displayed in the terminal emulator window when these tasks have been completed. Note, the CMX868 device is always reset and powered up at the beginning of the negotiation. The firmware only supports DTMF dialling. AT command echoing is an option available in the firmware and involves echoing the received characters sent by the PC. The firmware also provides the option of sending result codes to the PC. These responses can be in either an alpha or numeric form. The AT command set for the DE8681 is tabulated below. These commands can be entered on a PC running Windows terminal emulator software, such as the `HyperTerminal' program supplied with Windows 95/NT systems. The `HyperTerminal' Send Text File facility is useful for data transfer i.e. when the DE8681 has established a connection with a remote modem. This terminal emulator facility can also be used for sending AT command scripts to the DE8681. These scripts should consist of a single line multiple AT command, for example. ATH1@RE0=4929@RE6?@RE1=4567 (c) 2004 CML Microsystems Plc 15 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 Basic DE8681 AT Commands Command A Description Answer Command The modem will go off-hook and attempt to establish a connection with a remote modem. Syntax: ATA A/ Re-Execute Previous Command Line Re-executes the last issued command line. This command does not require the AT prefix or a carriage return. Syntax: A/ Bn Select Communications Standard Selects the communications standard specified by the parameter n. Syntax: ATBn Dn Dial Command This command directs the modem to go off-hook, dials according to the string entered and attempts to establish a connection with a remote modem. The n represents an ASCII string composed of dial digits and dial modifiers and must not exceed the 15 character buffer limit. The DTMF tone dialling digits include 0 through 9, A, B, C, D, and the symbols # and *. For example: ATD9,01621875500 En Echo Command Characters Syntax: ATEn (c) 2004 CML Microsystems Plc 16 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 Command Hn Switch Hook Control Syntax: ATHn Description Modifier Usage n=0 Instructs the modem to go on-hook (disconnect). n=1 Instructs the modem to go off-hook. In Identification Requests the modem to return its product identification information. Syntax: ATIn (c) 2004 CML Microsystems Plc 17 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 Command Sn=x Description S-Register Write Command for writing to an S-Register (See S-Register Table). Syntax: ATSn=x Vn Result Code Format Syntax: ATVn Xn Calling Characteristics Determines which set of responses and calling characteristics are used. Syntax: ATXn Zn Modem Reset Instructs the modem to reset the evaluation device and then reload the factory SRegister settings (See S-Register Table). Syntax: ATZn (c) 2004 CML Microsystems Plc 18 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 Extended DE8681 AT Commands Command &Fn Description Recall Factory Defaults Instructs the modem to reload the factory S-Register settings (See S-Register Table). Syntax: AT&Fn &Gn Guard Tone Select Selects the Guard tone to be transmitted with highband QAM or DPSK. Syntax: AT&Gn CML Specific DE8681 AT Commands Command @Fn Test Functions Syntax: AT@Fn Description (c) 2004 CML Microsystems Plc 19 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 Command @D Description DTMF Transmit (Only available on boards with a board mod state of 2 or higher) CMX868 will constantly transmit a selected DTMF tone dialling digit. Syntax: AT@D @RR CMX868 Device Reset Sends the General Reset Command to the CMX868 device. Syntax: AT@RR @Rn? CMX868 Register Read Command for displaying the contents of a CMX868 device register Syntax: AT@Rn? @Rn=x CMX868 Register Write Command for writing to a CMX868 device register. Syntax: AT@Rn=x (c) 2004 CML Microsystems Plc 20 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 S-Registers The following table gives a brief description of the available S-registers and their functions. Register range, units and factory profiles are also listed. S-Register Reg S0 Range 0-255 Units Rings Description Automatic answer - Number of rings until automatic answer. If the register is zero the modem will not automatically answer. Count incoming rings - This register is read only and contains the number of rings detected by the modem. Escape character value - This register defines an ASCII decimal value of the escape character. The default setting is an ASCII + and the escape sequence is +++. A value over 127 disables the escape sequence. Carriage return character - Contains the ASCII decimal value of the character recognised as the command line terminator. This character will also be sent at the end of result codes. Line feed character - Contains the ASCII decimal value of the character recognised by the modem as the line feed. The modem sends the line feed character after a carriage return only when word responses are sent. Backspace character - Contains the ASCII decimal value of the character recognised as a backspace. Wait time for blind dialling - Sets the length of time to pause after the modem goes off the hook before the modem dials the first digit of the telephone number. Wait for carrier after dial - Sets the length of time the modem waits for a carrier before returning on-hook. Factory Profiles `0' `1' (Default at Power up) 0 5 S1 0-255 Rings 0 0 S2 0-127 ASCII Decimal 43 43 S3 0-127 ASCII Decimal 13 13 S4 0-127 ASCII Decimal 10 10 S5 0-127 ASCII Decimal 8 8 S6 2-255 s 2 2 S7 1-255 s 50 50 (c) 2004 CML Microsystems Plc 21 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 S-Register Reg S8 Range 0-255 Units s Description Pause Time for Comma Dial Modifier Specifies the number of seconds to pause for each comma (,) encountered in a dial string. Reserved Lost carrier to hang up delay - Sets the length of time that the modem waits before hanging up after the loss of a carrier. This allows the modem to distinguish between disturbances that momentarily break the connection and the remote modem hanging up. DTMF tone duration - Defines the duration of DTMF tones for tone dialling. The length of pause between each DTMF tone is the same as this duration time. Escape code guard time - Specifies the minimum time before entry of the escape sequence. This value also dictates the acceptable entry speed (inter-character time) for each escape character. Reserved General options - provides the following functions: Bit 0 - Reserved Bit 1 - Echo command character, 0 Disables echoing (ATE0), 1 Enables echoing (ATE1) Bit 2 - Result code display, 0 Send responses (ATQ0), 1 Do not send responses (ATQ1) Bit 3 - Word or number responses, 0 Send number responses (ATV0), 1 Send word responses (ATV1) Bit 4 - Output format when reading CMX868 registers or S-registers, 0 Decimal, 1 Hex Bit 5, 6 - Reserved Bit 7 - Answer/originate operation, 0 Answer (ATA), 1 Originate (ATD) Reserved Reserved Reserved Factory Profiles `0' `1' (Default at Power up) 2 2 S9 S10 1-255 1-255 100ms 100ms 6 7 6 7 S11 5-25 10ms 10 20 S12 0-255 50ms 20 20 S13 S14 0-255 0-255 Decimal Decimal 0 138 0 128 S15 S16 S17 0-255 0-255 0-255 Decimal Decimal Decimal 0 0 0 0 0 0 (c) 2004 CML Microsystems Plc 22 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 S-Register Reg S18 Range 0-255 Units s Description General Purpose Timer - Used for various firmware functions. General Purpose Timer - Used for various firmware functions Reserved BERT functions disabled for EF8681 Version 1.0 firmware. BERT options - Provides the following functions: Bit 0 - BERT End, 0 Rx Board (AT@F4), 1 Tx Board (AT@F5) Bit 1 - BERT Operating Band (ignored for V23/Bell202 BERT operation), 0 Low, 1 High Bit 2, 3, 4, 5 - Reserved Bit 6,7 - BERT Scrambler/Descrambler, 11 Enabled (64 ones detect circuit enabled), 10 Enabled (64 ones detect circuit disabled), 00 Disabled Factory Profiles `0' `1' 30 30 S19 S20 S21 0-255 0-255 0-255 10ms Decimal Decimal 2 0 193 2 0 193 S22 0-255 Decimal Bit Mapped register - Provides the following functions: Bit 0, 1, 2, 3, 4 - Reserved Bit 5, 6, 7 - Calling Characteristics, 000 (ATX0), 100 (ATX1), 101 (ATX2), 110 (ATX3), 111 (ATX4) Bit Mapped register - Provides the following functions: Bit 0, 1, 2, 3, 4, 5 - Reserved Bit 6, 7 - Guard Tones (DPSK/QAM high band operation only), 00 None (AT&G0), 11 550Hz (AT&G1), 10 1800Hz (AT&G2) Bit Mapped register - Provides the following functions: Bit 0 - CMX868 Xtal Freq, 0 12.2880MHz, 1 11.0592MHz Bit 1 - CMX868 Tx and Rx Fixed Compromise Equalisers (used during negotiation and data transfer), 0 Enable, 1 Disable Bit 2 - CMX868 Auto Equaliser (DPSK operating modes, always enabled during V22bis QAM operation), 0 Disable, 1 Enable Bit 3, 4, 5, 6, 7 - Reserved 0 0 S23 0-255 Decimal 0 0 S24 0-255 Decimal 1 3 (c) 2004 CML Microsystems Plc 23 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 S-Register Reg S25 Range 0-255 Units Decimal Description Bit Mapped register - Provides the following functions: Bit 0, 1, 2 - CMX868 Tx Gain (used during negotiation, data transfer and BERT), 111 0dB, 110 -1.5dB, 101 -3.0dB, 100 4.5dB, 011 -6dB, 010 -7.5dB, 001 9.0dB, 000 -10.5dB Bit 3, 4, 5 - CMX868 Tx Data/Stop bits (used during data transfer), 111 8/2 bits, 110 8/1 bits, 101 7/2 bits, 100 7/1 bits, 011 6/2 bits, 010 6/1 bits, 001 5/2 bits, 000 5/1 bits Bit 6, 7 - CMX868 Tx Start-stop mode (used during data transfer), 00 Odd parity, 01 Even parity, 10 No parity Bit Mapped register - Provides the following functions: Bit 0, 1, 2 - CMX868 Rx Gain (used during negotiation, data transfer and BERT), 111 0dB, 110 -1.5dB, 101 -3.0dB, 100 4.5dB, 011 -6dB, 010 -7.5dB, 001 9.0dB, 000 -10.5dB Bit 3, 4, 5 - CMX868 Rx Data and Parity bits (used during data transfer), 111 8 data + parity, 110 8 data, 101 7 data + parity, 100 7 data, 011 6 data + parity, 010 6 data, 001 5 data + parity, 000 5 data Bit 6, 7 - CMX868 Rx USART (used during data transfer), 00 2.3% overspeed, 01 1% overspeed, 10 No overspeed Bit Mapped register - Provides the following functions: Bit 0, 1, 2, 3 - Reserved. Bit 4, 5, 6, 7 - Communication Standard, 0000 (ATB0), 0001 (ATB1), 0010 (ATB2), 0011 (ATB3), 0100 (ATB4), 0101 (ATB5), 0110 (ATB6), 0111 (ATB7), 1000 (ATB8), 1001 (ATB9) Factory Profiles `0' `1' 176 176 S26 0-255 Decimal 48 176 S27 0-255 Decimal 0 0 (c) 2004 CML Microsystems Plc 24 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 S-Register Reg S28 Range 0-255 Units Decimal Description Bit Mapped register - Provides the following functions: Bit 0, 1, 2 - CMX868 DTMF Twist level, 000 +2.0dB, 001 +1.0dB, 010 +1.5dB, 011 +2.5dB, 100 +3.0dB, 101 +3.5dB, 110 +4.0dB, 111 +4.5dB (do not use in conjunction with the 0dB Tx level setting) These DTMF twist settings are only effective on boards with a board mod state of 2 or higher. Bit 3, 4, 5, 6, 7 - Reserved. Factory Profiles `0' `1' 0 0 S29 0-255 Decimal Reserved 0 0 Modem Result Codes Numeric Response (Decimal) 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 AT Command Summary 1) The maximum command length is 48 characters, excluding the AT prefix and carriage return. 2) A user defined escape sequence (usually +++) is required to revert the modem from on-line (data transfer mode) to the command mode, to allow the user to issue AT commands to the PIC. 3) Every command except for A/ and the escape sequence must begin with the AT prefix and be entered by pressing a carriage return. 4) When the default command echoing and word result codes are enabled the firmware will send a LF character directly after a CR character to ensure the terminal emulator display is legible. 5) Commands which are not fully implemented will return the result code `NYI' (Not Yet Implemented). 6) Do not send AT commands to the Demonstration board until the previous result code (if enabled) has been received. Alpha Response OK CONNECT RING NO CARRIER ERROR NO DIAL TONE BUSY CONNECT 2400 CONNECT 1200 CONNECT 600 CONNECT 300 CONNECT 1200/75 CONNECT 75/1200 CONNECT 1200/150 CONNECT 150/1200 NYI (Not Yet Implemented) (c) 2004 CML Microsystems Plc 25 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 1.6.4 Software Description 1.6.4.1 In-Circuit Programming of PIC16LF876 TO ENTER PROGRAMMING MODE a) Remove power from board. b) Ensure that jumper JP1 is fitted. c) Apply 13Vdc programming voltage between pins 4(VPP) and 5(GND) of connector J5. d) Apply 5Vdc board supply voltage between socket pins 26 or 41 (GND) and 61(VDD). e) Connect a PC to the DE8681 using a standard RS-232 cable. f) Open a DOS window on the PC and run PICPROGF.EXE g) Reset the DE8681 board by operating SW1. PICPROGF.EXE This is supplied on CD-ROM as a self-documented executable file PICPROGF.EXE for a PC running DOS (either directly or as a DOS window in Windows 3.11 or `95). It is not recommended for use on Windows NT systems. Please note that this programming software does not meet the Arizona Microchip Technology verification requirements for a "production quality" programmer. Also, it does not support the programming of ID. The user interface consists of two windows. The top window contains the operating instructions and status information. The bottom window contains prompting and progress information plus user input. When the top window first appears the user will be prompted to enter the number of the serial communications port to which the DE8681 board is connected, and then, which device is to be programmed. For the DE8681 board select option 2, PIC16LF876. Once the user has entered this information, the following commands may be selected: Press F Press C Press E Press P Press V Press R Press A to load file to configure device. to block erase the device. to program target device. to verify target device. to read target device. to view contents of program data array. USING THE SOFTWARE - Press Esc to return to DOS. A new function from the above table can be selected whenever the >ok prompt appears in the bottom window. Notes: a) Programming files must be in the Intel hex format (.HEX) in order to be usable by this programming software. b) The PIC C supplied has a Configuration Word which is preset to 3D31H. This selects the configuration shown in the following table: (c) 2004 CML Microsystems Plc 26 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 PIC16LF876 Configuration Word - 3D31H Oscillator Watchdog Timer Powerup Timer Code Protect Brown Out Detect Low Voltage Programming Data EE Protect Flash Program Write Background Debug XT Off On Off Off Disabled Off Disabled Disabled The programming software currently defaults to 3D31H. Consult Arizona Microchip Technology for more information on the Configuration Word. c) The "block erase" command (E) erases the program memory and writes all 1's to the EEPROM. d) For each of the commands E, P, R and V the user will be prompted to manually reset the target C, by pressing the RESET switch (SW1) on the DE8681 board. This is because PIC programming always starts from location 0000 and the program counter can only be incremented. e) Pressing A will display the program data in the bottom window, formatted in pages of 48 consecutive locations. Use the TO LEAVE PROGRAMMING MODE a) Remove power from board (including the programming voltage, VPP). b) Leave jumper JP1 fitted. c) Apply VDD (3 or 5Vdc) to the board. (c) 2004 CML Microsystems Plc 27 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 1.6.4.2 Terminal Emulator Users will need to run a suitable terminal emulator on their PC in order to communicate with the PIC C on the DE8681. `HyperTerminal', which is supplied with the Windows 95/NT installations, is suitable for this purpose. HyperTerminal Setup Emulation VT100 ASCII Character set ASCII Receiving: COM Port Settings: Wrap lines that exceed terminal width. Bits per second Data bits Parity Stop bits Flow Control 19,200 8 None 1 Hardware 1.6.5 Additional Information 1.6.5.1 AT Command Text Files To allow evaluation tests to be quickly and easily repeated it may be useful to create text files containing single line multiple AT commands. Commands can be transferred to the PIC C via the `HyperTerminal' send text file facility. Note, multiple text files may be required to perform a test if any command lines exceed 48 characters. 1.6.5.2 Sending Text Files using `HyperTerminal' The following is a description of how to send text files to the DE8681 using `HyperTerminal'. a) Select the Transfer menu b) Select Send Text File (c) 2004 CML Microsystems Plc 28 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 c) Select the required file from the Send Text File window 1.6.5.3 Negotiation and Data Transfer Modem negotiation (handshaking) may be aborted by pushing any key prior to entering data transfer mode. During data transfer mode the user can revert to on-line AT command mode by typing the escape code sequence (+++). The escape code guard time (based on S12) must have expired to successfully access this mode. Whilst in on-line AT command mode the board to remote modem connection may be aborted by typing ATH0 (instructs modem to go on-hook). Alternatively the user can enter relevant AT commands or return to data transfer mode by using the ATO command. The firmware only supports asynchronous data transfer. Receiver USART overspeed settings specified in S-Register, S26, only apply to DPSK/QAM operating modes. Transmitter Guard Tone settings specified in S-Register, S23, only apply to DPSK/QAM answering modes. If the carrier is lost (during data transfer) or negotiation is aborted by the user, the firmware will send the General Reset Command to the CMX868 device. This action will cause the DE8681 demonstration board to hang up and powersave the CMX868 device. The data transfer firmware does not contain any retrain code. This process is sometimes performed by modems when signal distortion or line noise is detected which may threaten data integrity. The receive auto equaliser function can be enabled via the S24 register. This S24 register setting only applies to DPSK modes of operation. The CMX868 firmware for V22bis always enables the receive auto equaliser half way through the negotiation phase. (c) 2004 CML Microsystems Plc 29 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 1.6.5.4 Example AT Commands for Hayes Optima 336 Modem (not supplied) Setup V.22bis Protocol - AT&FB30X1Q0E1V1L0N0W2S37=6S95=42 V.22 Protocol - AT&FB0X1Q0E1V1L0N0W2S37=5S95=42 1.6.6 Example DE8681 Modem Tests 1.6.6.1 Set up DE8681 to Automatically Answer a V.22 Call from a Remote Modem 1. Select V.22 communication standard (default is V.22 bis). Command : ATB1 (c) 2004 CML Microsystems Plc 30 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 1.6.6.3 Set up DE8681 to Originate V.22 bis Call to a Remote Modem Configure DE8681 to dial out using a blind dialling method with DTMF tone duration of 150ms. 1. Select V.22 bis communication standard (default is V.22 bis). Command : ATB0 1.6.7 Example DE8681 Device Evaluation Tests The following information shows example text files (not supplied) that can be created by the user for DE8681 Evaluation Mode Tests. Description : Command : Instructs DE8681 to reset and powerup the CMX868 evaluation device. AT@RE0=4480@F2@RE0=4352 B11 0 No LB B10 0 Equ Enable B9 0 On Hook B8 1 Powered Up B7 1 Reset B6 0 IRQN O/P Disabled B5 0 B4 0 B3 B2 0 0 No IRQ Mask B1 0 B0 0 General Control Register ($E0) = 1180 Hex B15 B14 B13 B12 0 0 0 1 11.0592 Xtal General Control Register ($E0) = 1100 Hex B15 B14 B13 B12 0 0 0 1 11.0592 Xtal B11 0 No LB B10 0 Equ Enable B9 0 On Hook B8 1 Powered Up B7 0 Norm B6 0 IRQN O/P Disabled B5 0 B4 0 B3 B2 0 0 No IRQ Mask B1 0 B0 0 The following information shows example AT commands for simple DE8681 demonstration board tests. All tests assume the CMX868 is powered up, as shown above. (c) 2004 CML Microsystems Plc 31 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 Test 1 Description : Command : Instructs DE8681 to go off-hook and transmit a 1209Hz tone (Tx Gain = 0dB). ATH1@RE1=7685 B11 1 B10 B9 1 1 Tx Level = 0dB B8 0 B7 0 Unused B6 0 B5 0 B4 0 B3 B2 B1 0 1 0 Tx 1209Hz Fixed Tone B0 1 Tx Mode Register ($E1) = 1E05 Hex B15 B14 B13 B12 0 0 0 1 Tx Mode = DTMF/Tones Test 2 Description : Command : Instructs DE8681 to go off-hook and transmit a 1209Hz tone (Tx Gain = -10.5dB). ATH1@RE1=4101 B11 B10 B9 0 0 0 Tx Level = -10.5dB B8 0 B7 0 Unused B6 0 B5 0 B4 0 B3 B2 B1 0 1 0 Tx 1209Hz Fixed Tone B0 1 Tx Mode Register ($E1) = 1005 Hex B15 B14 B13 B12 0 0 0 1 Tx Mode = DTMF/Tones Test 3 Description : Command : Instructs DE8681 to go off-hook and transmit a 2100Hz tone (Tx Gain = 0dB). ATH1@RE1=7690 B12 1 B11 1 B10 B9 1 1 Tx Level = 0dB B8 0 B7 0 Unused B6 0 B5 0 B4 0 B3 B2 B1 1 0 1 Tx 2100Hz Fixed Tone B0 0 Tx Mode Register ($E1) = 1E0A Hex B15 0 B14 B13 0 0 Tx Mode = DTMF/Tones Test 4 Description : Command : Instructs DE8681 to go off-hook and transmit V.23 continuous 1s at 75bps. ATH1@RE1=19995 B11 1 B10 B9 1 1 Tx Level = 0dB B8 0 B7 0 No Guard Tone B6 B5 0 0 Scrambler Disabled B4 B3 1 1 Sync Mode B2 0 B1 1 Tx Cont 1's B0 1 Tx Mode Register ($E1) = 4E1B Hex B15 B14 B13 B12 0 1 0 0 Tx Mode = V.23 FSK 75 bps (c) 2004 CML Microsystems Plc 32 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 Test 5 Description : Instructs DE8681 to go off-hook and transmit two DTMF digits (`A' then `B' with 100ms duration/separation). Command : ATH1@RE1=7709@F2@RE1=7680@F2@RE1=7710@F2@RE1=7680 B11 1 B10 B9 1 1 Tx Level = 0dB B8 0 B7 0 Unused B6 0 B5 0 B4 1 B3 1 B2 1 Tx DTMF `A' B1 0 B0 1 Tx Mode Register ($E1) = 1E1D Hex B15 B14 B13 B12 0 0 0 1 Tx Mode = DTMF/Tones Tx Mode Register ($E1) = 1E00 Hex B15 B14 B13 B12 0 0 0 1 Tx Mode = DTMF/Tones Tx Mode Register ($E1) = 1E1E Hex B15 B14 B13 B12 0 0 0 1 Tx Mode = DTMF/Tones B11 1 B10 B9 1 1 Tx Level = 0dB B8 0 B7 0 Unused B6 0 B5 0 B4 0 B3 0 B2 0 Tx No Tone B1 0 B0 0 B11 1 B10 B9 1 1 Tx Level = 0dB B8 0 B7 0 Unused B6 0 B5 0 B4 1 B3 1 B2 1 Tx DTMF `B' B1 1 B0 0 Test 6 Description : Command : Set up CMX868 for receiving DTMF, then wait for five DTMF digits. AT@RE0=5953@RE2=7681@RE6?@F7@F7@F7@F7@F7 B11 0 No LB B10 1 Equ Disable B9 1 Off Hook B8 1 Powered Up B7 0 Norm B6 1 IRQN O/P Enabled B5 0 B4 B3 B2 B1 0 0 0 0 DTMF Detect IRQ Mask B0 1 General Control Register ($E0) = 1741 Hex B15 B14 B13 B12 0 0 0 1 11.0592 Xtal Rx Mode Register ($E2) = 1E01 Hex B15 B14 B13 B12 0 0 0 1 Rx Mode = DTMF/Tones B11 1 B10 B9 1 1 Rx Level = 0dB B8 0 B7 0 B6 0 B5 0 B4 0 Detect DTMF B3 0 B2 0 B1 0 B0 1 1.6.8 Trouble Shooting Some terminal emulators have been found not to support full hardware flow control when transferring text files. This could result in data loss when using this facility. If this problem is experienced users should try using a different terminal emulator To ensure successful negotiation and data transfer between the DE8681 and third party modems, users should ensure their third party modem is configured to the correct protocol (see third party AT command documentation). Note, any sudden loss of the 2-wire line during data transfer will result in loss of carrier and therefore the demonstration board will hang up and display the NO CARRIER message. However, due to the lost carrier to hang up delay (S10), a short burst of corrupt characters (noise generated) will be observed on the HyperTerminal window before the NO CARRIER message is displayed. These corrupt characters can sometimes match control characters and therefore modify HyperTerminal's behaviour. The user is advised to restart HyperTerminal if this happens. (c) 2004 CML Microsystems Plc 33 UM8681/3 CMX868 Reference Design and Demonstration Board DE8681 1.7 1.7.1 Performance Specification Electrical Performance 1.7.1.1 Absolute Maximum Ratings Exceeding these maximum ratings can result in damage to the DE8681. Min. -0.3 -0.3 -20 -40 -30 Max. 7.0 VDD + 0.3 +20 +125 +85 Units V V mA C C Supply (VDD - VSS) Voltage on any connector pin to VSS Current into or out of any socket modem connector pin other than VDD, VSS, TIP and RING Storage Temperature Operating Temperature 1.7.1.2 Operating Limits Correct operation of the DE8681 outside these limits is not implied. Notes Supply (VDD - VSS) Operating Temperature 1.7.1.3 Operating Characteristics For the following conditions unless otherwise specified: Evaluation Device Xtal Frequency = 11.0592MHz 0.01% (100ppm) VDD = 3.0V or 5.0V, Tamb = +25C. Notes DC Parameters IDD (socket modem alone - idle) IDD (demonstration board - idle) Notes: 1. 1 1 Min. Typ. 12.0 30.0 Max. Units mA mA Min. 2.7 +10 Max. 5.5 +35 Units V C DCD, TXD, RXD, DTR, and HOOK LEDs off. (c) 2004 CML Microsystems Plc 34 UM/8681/3 CMX868 Reference Design and Demonstration Board DE8681 CML does not assume any responsibility for the use of any circuitry described. No IPR or circuit patent licences are implied. CML reserves the right at any time without notice to change the said circuitry and any part of this product specification. Evaluation kits and demonstration boards are supplied for the sole purpose of demonstrating the operation of CML products and are supplied without warranty. They are intended for use in a laboratory environment only and are not for re-sale, end-use or incorporation into other equipments. Operation of these kits and boards outside a laboratory environment is not permitted within the European Community. All software/firmware is supplied "as is" and is without warranty. It forms part of the product supplied and is licensed for use only with this product, for the purpose of demonstrating the operation of CML products. Whilst all reasonable efforts are made to ensure that software/firmware contained in this product is virus free, CML accepts no resonsibility whatsoever for any contamination which results from using this product and the onus for checking that the software/firmware is virus free is placed on the purchaser of this evaluation kit or development board. www.cmlmicro.com For FAQs see: www.cmlmicro.com/products/faqs/ For a full data sheet listing see: www.cmlmicro.com/products/datasheets/download.htm For detailed application notes: www.cmlmicro.com/products/applications/ CML Microcircuits (UK ) Ltd CML Microcircuits (USA) Inc. 4800 Bethania Station Road, Winston-Salem, NC 27105 - USA. CML Microcircuits (Singapore)Pte Ltd COMMUNICATION SEMICONDUCTORS Oval Park, Langford, Maldon, Essex, CM9 6WG - England. No 2 Kallang Pudding Road, #09 to 05/06 Mactech Industrial Building, Singapore 349307 No. 218, Tian Mu Road West, Tower 1, Unit 1008, Shanghai Kerry Everbright City, Zhabei, Shanghai 200070, China. Tel: +86 21 6317 4107 +86 21 6317 8916 Fax: +86 21 6317 0243 Sales: cn.sales@cmlmicro.com.cn Technical Support: sg.techsupport@cmlmicro.com Tel: +44 (0)1621 875500 Fax: +44 (0)1621 875600 Sales: sales@cmlmicro.com Technical Support: techsupport@cmlmicro.com Tel: +1 336 744 5050, 800 638 5577 Fax: +1 336 744 5054 Sales: us.sales@cmlmicro.com Technical Support: us.techsupport@cmlmicro.com Tel: +65 6745 0426 Fax: +65 6745 2917 Sales: sg.sales@cmlmicro.com Technical Support: sg.techsupport@cmlmicro.com |
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