I have a Crystal Castles board where the 74LS244 at 2F for the program memory, has floating input pins (no high or low) and the output pins are stuck low. From what I read, inputs should match outputs. Both pins OE1 and OE2 are stuck high(according to truth table active is low). The output pins from the EPROMS to the inputs on 2F are also floating. Also 2J (74LS244) in the Bit-Mode read/write section also has input and out put pins that dont match. Inputs are stuck low but outputs are flipping. That one confuses me. Checked the /reset on cpu and its low which should mean its in reset. Watchdog is high, so that isnt on. R/W on cpu shows high, so if I'm correct its in read mode since the W has a line over it in the schematics and the R doesn't. (Line over something means active when not high). There are two 74LS244s at 1B and 1C. Their inputs come from the CPU and their outputs go through the address decoder section and on to the inputs of the EPROMs. 1B takes one half of the address lines and 1C takes the other half. 1Bs input and outputs match, their stuck low. 1Cs inputs and outputs also match, their stuck high. Both the OE1 and OE2 pins on these chips are flipping. Any feedback would be great. I think either 2F or 2J are causing an issue. I'm wondering since its in read mode if its having trouble reading the EPROMS.
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