300 BPS DCM-7 Modem (260-1394) Dip Switches Faxback Doc. # 7001 DIP switches control the DCM-7's power-up condition. These switches must be set before you turn the power ON. First, you will have to decide whether you want to use the Modem in the Tandy protocol mode of Hayes protocol mode. If you are using Tandy communications software, you will want to set it for Tandy protocol. For use with Hayes communications software, set it to the Hayes protocol mode. (The Tandy 1000s, 1200 and 3000 personal computers can be used with either communications software.) HAYES PROTOCOL When you want to use your DCM-7 in Hayes protocol mode, position Switch 7 to OFF. In this protocol mode, the remaining switches function differently from those in Tandy protocol. Refer to the table below for suggested switch settings in Hayes protocol mode. SEND RESULT CODES────────────────┐ ┌─────────────────────COMMAND ECHO ON │ │ NUMERIC RESULT CODES────────┐ │ │ ┌─────────────AUTO ANSWER ENABLE │ │ │ │ TRUE CARRIER ──────────┐ │ │ │ │ ┌────────────HAYES PROTOCOL │ │ │ │ │ │ TRUE DTR ──────┐ │ │ │ │ │ │ ┌─────── NO FUNCTION │ │ │ │ │ │ │ │ ┌─┬──┬─┬──┬─┬──┬─┬──┬─┬──┬─┬──┬─┬──┬─┬──┬─┐ ON │ ├──┤ ├──┤ │ │ ├──┤ ├──┤ │ │ ├──┤ ├──┤ │ /\ │ │ │ │ │ ├──┤ │ │ │ │ ├──┤ │ │ │ │ │ │ └──┘ └──┘ └──┘ └──┘ └──┘ └──┘ └──┘ └──┘ │ \/ │ 1 2 3 4 5 6 7 8 │ OFF │ │ │ │ └─────────────────────────────────────────┘ │ │ │ │ │ │ │ │ FORCED DTR ──────┘ │ │ │ │ │ │ └─────── NO FUNCTION │ │ │ │ │ │ FORCED CARRIER ────────┘ │ │ │ │ └────────────TANDY PROTOCOL │ │ │ │ VERBAL RESULT CODES─────────┘ │ │ └────────────AUTO ANSWER DISABLE │ │ NO RESULT CODES──────────────────┘ └────────────────────COMMAND ECHO OFF SWITCH NUMBER POSITION FUNCTION 1 ON Forced DTR. OFF True DTR. 2 ON Forced carrier detect. OFF True carrier detect. 3 ON Displays verbal result codes. OFF Displays numeric result codes. 4 ON Result codes disabled. Disables Switch 3. OFF Result codes enabled. Enables Switch 3. 5 ON Command echo disable. OFF Command echo enable. 6 ON Auto-answer disable. OFF Auto-answer enable. 7 OFF Should be OFF. Sets the Modem to Hayes protocol mode. 8 OFF Should be OFF. No Function. For easy operation, position Switch 5 to OFF to echo the command line. Set Switch 4 to OFF and Switch 3 to ON to send the verbal result codes to the screen. TANDY PROTOCOL When you select Tandy protocol mode, set DIP switch 7 to ON. This tells the Modem to set other DIP switch functions as listed above. Refer to the list above for the suggested switch settings in this mode. NO FUNCTION ────────────────────┐ ┌────────────────────── NO FUNCTION │ │ NO FUNCTION ───────────────┐ │ │ ┌───────────────── AUTO ANSWER │ │ │ │ DISABLE TRUE CARRIER ──────────┐ │ │ │ │ ┌────────────HAYES PROTOCOL │ │ │ │ │ │ TRUE DTR ──────┐ │ │ │ │ │ │ ┌─────── NO FUNCTION │ │ │ │ │ │ │ │ ┌─┬──┬─┬──┬─┬──┬─┬──┬─┬──┬─┬──┬─┬──┬─┬──┬─┐ ON │ ├──┤ ├──┤ ├──┤ ├──┤ ├──┤ ├──┤ │ │ ├──┤ │ /\ │ │ │ │ │ │ │ │ │ │ │ │ │ ├──┤ │ │ │ │ └──┘ └──┘ └──┘ └──┘ └──┘ └──┘ └──┘ └──┘ │ \/ │ 1 2 3 4 5 6 7 8 │ OFF │ │ │ │ └─────────────────────────────────────────┘ │ │ │ │ │ │ │ │ FORCED DTR ──────┘ │ │ │ │ │ │ └─────── NO FUNCTION │ │ │ │ │ │ FORCED CARRIER ────────┘ │ │ │ │ └────────────TANDY PROTOCOL │ │ │ │ NO FUNCTION ───────────────┘ │ │ └───────────────── AUTO ANSWER │ │ ENABLE NO FUNCTION ────────────────────┘ └────────────────────── NO FUNCTION SWITCH NUMBER POSITION FUNCTION 1 ON Forced DTR (Data Terminal Ready). Modem accepts command from the local computer without a DTR signal. OFF True DTR. Modem is OFF until it receives a true DTR signal from the computer. 2 ON Forced carrier. Modem assumes force carrier detect* and disables the G command. OFF Forced/True carrier. Modem assumes forced carrier detect and true carrier detect** according to the G command input. 3 OFF Should be OFF. No function. 4 OFF Should be OFF. No function. 5 OFF Should be OFF. No function. 6 ON Auto-answer enable. Modem assumes auto-answer upon power-up. OFF Auto-answer disable. Modem assumes auto-originate upon power-up. 7 ON Should be ON. Tandy. Set the Modem to Tandy protocol mode. 8 OFF Should be OFF. No function. * Forced carrier detect...Modem issues a forced carrier signal to the local computer as soon as the power is turned ON. ** True carrier detect...Modem will be off until it receives true carrier from the remote computer. DIP Switch 2 interlocks with DIP Switch 6 as follows: ┌──┐ ┌──┐ OFF /\ │ │ │ │ Modem assumes auto-answer with forced carrier ├──┤ ├──┤ detect. ON \/ └──┘ └──┘ 2 6 ┌──┐ ┌──┐ Modem assumes auto-originate with forced carrier OFF /\ │ │ ├──┤ detect. ├──┤ │ │ ON \/ └──┘ └──┘ 2 6 ┌──┐ ┌──┐ OFF /\ ├──┤ │ │ Modem assumes auto-answer with true carrier │ │ ├──┤ detect at power-on. The true/forced carrier ON \/ └──┘ └──┘ condition can be changed with the G command. 2 6 ┌──┐ ┌──┐ OFF /\ ├──┤ ├──┤ Modem assumes auto-originate with forced carrier │ │ │ │ detect at power-on. The true/forced carrier ON \/ └──┘ └──┘ condition can be changed with the G command. 2 6 COMMUNICATIONS PROTOCOL The following criteria must be met before computer-to-computer communication can occur. 1. Both computers must have the same communications protocol: 300 bps Word length (7 bits or 8 bits) Parity (even, odd, or none) Number of stop bits (1 or 2) See your computer owner's manual for instructions on setting the communications protocol. 2. One modem must be in ORIGinate mode and the other must be in ANSwer mode. Usually, when you call another computer, you should be in ORIGinate mode. When you receive a call, you should be in ANSwer mode. The DCM-7 provides automatic and manual operations in both originate and answer modes. When opened for programming by the wake-up or attention code sequence, it will automatically synchronize the speed rate, word length, parity, and stop-bit numbers (communications protocol) of your computer system. HELPFUL TIP: When you use your DCM-7 for the first time or when you seem to be getting garbled data, use the self-test mode to help you find the cause of the problem. Refer to the section on self-test mode in Appendix A, Tandy Protocol reference or in Appendix B, Hayes protocol reference. If you plan to use the DCM-7 in Tandy protocol mode only, you may skip Chapter 3 and Appendix B. However, if you intend to use it in Hayes protocol mode only, you may disregard Chapter 2, and Appendices A and D. Refer also to the operation manual which accompanies your communications software package. (css/BKL-02/07/96)