Acorn Computers Limited Winchester disk 110, Service Manual, Page: 25 / 43

Test pin 11 IC2 with a scope and check that the waveform is not stuck either
high or low. It should look like the one shown in figure 5.
7.2.3 &FC41 read status
Run the following program:
10DIM P% 10
20[
30.a
40LDA &FC41
50JMP a
60]
70CALL a
Test pin 1 IC4 with a scope and check that the waveform is not stuck either
high or low. It should look like the one shown in figure 4.
7.2.4 &FC42 write select
Run the following program:
10DIM P% 10
20(
30.a
40STA &FC42
50JMP a
60]
70CALL a
Test pin 11 IC11 with a scope and check that the waveform is not stuck
either high or low. It should look like the one shown in figure 4.
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