8-line to hex reader

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1

I would like to be able to read 8 address lines and output a hex byte value representing the state of those 8 address lines, e.g., 0111 1110 would show as 0x7E. Or, using two devices, read 4 address lines each and output a hex nibble value each. Does an IC exist that either does this function or can be coerced into performing part of the function? Thanks.

2

What do you mean by “show”? You can easily do this with any small micro (PIC, AVR, MSP, etc. ) that has enough pins for the 8 input bits and the display or output device (you can always add a latching shift register to save on the input pins).

Back in the old days, we would use a 74S89 PROM or DM9368 hex-to-7segment decoder to drive a display or a TIL-311 display that had the decoder built in. If you don’t mind HELP instead of A-F, even the 7447 would work.

/mike

3

Thanks, Mike.

4

Consider the 74lv(or hc)165 8 bit parallel in serial out shift register.

5

Thanks, J. I’ll consider sending its output to a 595 and dual LED.