Quote:
Originally Posted by SiriusHardware
Mark1960 has pointed out, correctly, that I could have used 8 * voltage dividers (two resistors on each data pin) to divide the voltage out from the EPROM by about two-fifths: For example 1K8 in series with 3K3 down to 0V would give about the right division ratio, 16 resistors altogether.
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I don’t think that was me. I think it was ortek_service.
You might try a 74ac244 or 74ac541 powered at 3v3, inputs would be 5v tolerant.
Schottky diodes from inputs to 3.3v supply might stop the input going above the supply together with a current limit resistor.
Most ttl families have a diode to protect the input going below 0v, but not to go above the supply, but the 74ac family is 5v input tolerant and at 3v3 the input levels are similar to 5v ttl.