| |
| Pulsing
each address line individually |
| |
In the event an addressing error is suspected, the
following test group can troubleshoot and verify each address line individually.
Testing each position is done by selecting the appropriate test, and
measuring the response with an oscilloscope, or the external probe. Selecting
"cycle instruction" will continuously run the last test
requested, so that the data will show as a stream of pulses on the address
line under test, while leaving
all other address lines in the "low" state.
|
 |
|
< These tests require external measurement. > |
| |
| These
tests can also be performed using the Ms
Pacman Troubleshooting Tool |
| |
|
The group of tests shown above are applicable to any microprocessor based
board, and are "generic" types of tests, only because the name
of each instruction reflect this. |
Two examples of changing these instructions into the specific board tests
for Galaga and Ms Pacman-type circuitry follow. The tests have been
renamed to the point in the circuit as they pertain to each board.
|
