UNIDENTIFIED 2400BS MODEM Card Type Modem (asynchronous) Chip Set Unidentified Maximum Data Rate 2400bps Data Bus 8-bit ISA Data Modulation Protocol Bell 103/212A ITU-T V.21, V.22, V.22bis [Image] CONNECTIONS Function Label Function Label Line in CN1 Volume R1 Line out CN2 SERIAL PORT ADDRESS AND INTERRUPT Setting Setting SW1/1 SW1/2 COM1 (3F8h) IRQ 4 On On COM2 (2F8h) IRQ 3 Off On COM3 (3E8h) IRQ 4 On Off COM4 (2E8h) IRQ 3 Off Off Proprietary AT Command Set BIT-MAPPED REGISTER S14 Format AT [cmds] S14=n [cmds] Default: 170 Range: 0-174 Unit: Bit-mapped Description: Controls echo, result codes and display, dial mode, and answer/originate mode. Bit Value Function 0 0 Not used 1 0 Command echo disabled 1 Command echo enabled 2 0 Result codes enabled 1 Result codes disabled 3 0 Display result codes in numeric format 1 Display result codes in verbose format 4 0 Not used 5 0 Tone dial enabled 1 Pulse dial enabled 6 0 Not used 7 0 Answer mode enabled 1 Originate mode enabled BIT-MAPPED REGISTER S21 Format AT [cmds] S21=n [cmds] Default: 48 Range: 0-252 Unit: Bit-mapped Description: Selects CTS/DCD/DSR signals, low DTR action, and the long space disconnect function. Bit Value Function 1, 0 0 Not used 2 0 CTS follows RTS 1 CTS forced high 4, 3 00 DTR signal ignored 01 Modem goes to command mode on low DTR 10 Modem disconnects on low DTR; Auto-Answer is disabled. 11 Modem is initialized on low DTR 5 0 DCD forced high 1 DCD normal 6 0 DSR forced high 1 DSR normal 7 0 Long space disconnect function disabled 1 Long space disconnect function enabled BIT-MAPPED REGISTER S22 Format AT [cmds] S22=n [cmds] Default: 118 Range: 0-255 Unit: Bit-mapped Description: Controls speaker volume and controls, limits results codes, and make/break ratio. Bit Value Function 1, 0 00 Off volume 01 Low level volume 10 Medium level volume 11 High level volume 3, 2 00 Speaker off 01 Speaker off on carrier 10 Speaker always on 11 Speaker on during handshake 6, 5, 4 000 Basic result codes only enabled 100 Basic and connection speed result codes enabled 101 Basic and connection speed result codes and dialtone detection enabled 110 All result codes except dialtone detection enabled 111 All result codes enabled 7 0 39/61ms at 10pps (North America) 1 33/67ms at 10pps (Europe) BIT-MAPPED REGISTER S23 Format AT [cmds] S23=n [cmds] Default: 6 Range: 0-183 Unit: Bit-mapped Description: Grants/denies remote digital loopback, controls DTE rate and parity, and sets guard tone. Bit Value Function 0 0 Remote digital loopback denied 1 Remote digital loopback allowed 2, 1 00 Sets serial port speed to 0-300bps 10 Sets serial port speed to 1200bps 11 Sets serial port speed to 2400bps 3 0 Not used 5,4 00 Parity even 01 Space Parity 10 Parity odd 11 Mark Parity 7, 6 00 Guard tone disabled 01 Guard tone 550Hz enabled 10 Guard tone 1800Hz enabled BIT-MAPPED REGISTER S27 Format AT [cmds] S27=n [cmds] Default: 64 Range: 0-68 Unit: Bit-mapped Description: Selects line type, and ITU-T/Bell modes. Bit Value Function 1, 0 0 Not used 2 0 Switched line 1 Leased line 5 - 3 0 Not used 6 0 ITU/T mode 1 Bell mode TEST MODES Format AT [cmds] S16=n [cmds] Default: 0 Range: 0-125 Unit: Bit-mapped Description: Controls loopback tests, analog, digital, remote digital, and self tests. Bit Value Function 0 0 Local analog loopback not in progress 1 Local analog loopback in progress 1 0 Not used 2 0 Local digital loopback not in progress 1 Local digital loopback in progress 3 0 Modem not in remote digital loopback 1 Remote digital loopback in progress 4 0 Remote digital loopback not requested 1 Remote digital loopback requested 5 0 Remote digital loopback w/ self-test not in progress 1 Remote digital loopback w/ self-test in progress 6 0 Local analog loopback w/ self-test not in progress 1 Local analog loopback w/ self-test in progress