Re: The Transam Triton Personal Computer
Fired up the Triton main board today and as expected its not working.
Based on the first look see I have found a number of problems:-
The Keyboard is putting -12v on some of the keyboard buffer TTL data input pins IC49.
IC49 (74LS244) is holding DB8 to near zero but if the Keyboard is unplugged it returns to +5 but DB8 is connected to its input pin 11 even though the select pins and 19 are high.
The VDU chips seams dead IC61 (SFC96364) but there is a clock on pin 2, is this chip still available ?
Has anyone got a example of what the waveform should look like on pin 2 ?
This is going to be more of a challenge than I expected.
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