Southwest Specialty Products 6800 manual Swtbug Installation, Swtbug Operation, Reset

SWTBUG® INSTALLATION

SWTBUG® is a MOS device and MOS integrated circuits are susceptible to damage by static electricity. Although some degree of protection is provided internally within the integrated circuits, their cost demands the utmost in care. Before opening and/or installing SWTBUG® you should ground your body and all metallic tools coming into contact with the leads, thru a 1M ohm

¼watt resistor. The ground must be an “earth” ground such as a water pipe, and not the circuit board ground. As for connection to your body, attach a clip lead to your watch or metal ID bracelet. Make absolutely sure that you have the resistor connected between you and the “earth” ground, otherwise you will be creating a dangerous shock hazard. Avoid touching the leads of the integrated circuits any more than necessary when installing it, even if you are grounded. Static electricity should be an important consideration in cold, dry environments. It is less of a problem when it is warm and humid.

When using SWTBUG® with an MP-A processor card, one board change is necessary since SWTBUG® is a full 1 K ROM and MIKBUG® was a 1/2K device, If this ROM is replacing MlKBUG, remove MIKBUG® from its socket. On the back side of the MP-A board you will notice that pin 15 of IC-2 (ROM) is grounded. The land coming from pin 15 should be broken and a wire added as shown below.

SWTBUG® should now be installed in the socket for IC-2. Be sure to orient the ROM correctly when re-installing. The semicircle notch or dot should match with the MP-A board’s component layout drawing. When installing SWTBUG® in the MP-A2 processor board no board modifications are necessary. Follow the instructions supplied with the MP-A2 instruction set.

SWTBUG® OPERATION

The SWTBUG® firmware enables the computer to communicate with a terminal to perform various programming and debugging functions. SWTBUG® will communicate with a terminal via either a MP-C control interface or MP-S ACIA serial interface on I/O port 1. An optional MP-C interface can be installed on I/O port 0 for punch and load functions. Although SWTBUG® is essentially compatible with MIKBUG, be sure to read the COMPATIBILITY section before running any programs written for MIKBUG. Below is a detailed description of each SWTBUG® command.

RESET

Upon receiving a RESET command, as during power up, SWTBUG® will initialize the system to receive commands from a terminal. When the RESET button is pushed, control will transfer to location E0D0 of SWTBUG®. The RESET button should be used for exiting loops or malfunctioning programs. After resetting, the computer should respond with a carriage return, line feed and a $ sign. At this point, SWTBUG® is waiting for commands. If breakpoints are being used, the RESET function will not disable breakpoints. The BREAKPOINT function should be referenced for additional information.

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