I have had a chance to do a bit more investigation on this and may have found something.
It seems as though IC29, the flip flop that controls the FDD (selection and mechanics I gather), may not be quite right. It seems like the INUSE signal that lights up the LED is working ok, but the MOTORON is not being set correctly.
The trace below shows that although /INUSE takes the value of BD6 when it is triggerd by the CLK, /MOTORON does not seem to be getting set LOW. I find it a bit strange that the Flip Flop would be 'partly' working, but looking at the schematic, there is not anything else I can find that could be pulling the MOTORON line up.
Any suggestions much appreciated, I am thinking pull out IC29 and replace it?
Cheers!
Nic
It seems as though IC29, the flip flop that controls the FDD (selection and mechanics I gather), may not be quite right. It seems like the INUSE signal that lights up the LED is working ok, but the MOTORON is not being set correctly.
The trace below shows that although /INUSE takes the value of BD6 when it is triggerd by the CLK, /MOTORON does not seem to be getting set LOW. I find it a bit strange that the Flip Flop would be 'partly' working, but looking at the schematic, there is not anything else I can find that could be pulling the MOTORON line up.
Any suggestions much appreciated, I am thinking pull out IC29 and replace it?
Cheers!
Nic
Statistics: Posted by nicf82 — Sun Mar 31, 2024 9:36 pm