AFTER ERROR OF MISSING PULLUP, STILL HAVE ERRONEOUS BEHAVIOR
The card was producing the 1.9 ms and 50 ms output pulses now. More importantly, the interrupt level 3 request (IL3) was not incorrectly high before commands were issued. I saw the busy status emitted when the XIO Sense Device was issued.
What was wrong was the behavior of both busy and IL3. I saw the flipflop turn on, emitting IL3, when I requested a Drum Up move. However, the line dropped after 100 ms when it should have been latched on until an XIO Sense Device with bit 15 was issued.
This is incorrect on three levels. First, the flipflop should not turn off by itself. Second, the timing suggests that even though I was issuing one of the 1.9 ms actions, the other pair of timers produced two 50 ms actions; the Drum and Carriage movement commands should create two 1.9 ms intervals. Third, the intervals, whether 50 or 1.9, have no path that should reset the IL3 flipflop.
There might be a short between wires, since this was a very bodged prototype, or a bad gate, but in any case the behavior is incorrect. I will check this further when I get back from a family trip early next week.
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