NetBurner Community Forum

First off, I am a software guy who dabbles in hardware. That said, I have questions about what digital chip series are compatible with a 5270.

The planned external components are:
2 (R/W) quadrature encoders (3st - LVTTL)
2 (R) keypad encoders (5V TTL)
1 (R) 8 bit ADC (5v TTL)
1 (W) 4-16 decoder (*) (address decoding)
2 (R/W) 8 bit latches (*)
2 (R/W) multiplexed interrupt lines (*)

(*) I can make them whatever I need to.

So my question is what series of chips should(could) I use. I was planning on using 'LV' series for everything, with the exception of using 74LVC4245's to translate the 5V signals to 3.3V.

I just saw the external bus app note and it uses an 'HC' series chip. I thought that the HC series used cmos logic levels, which from what I understand are incompatible with LVTTL.

What are my options and what are the best choices?

TIA

I though HC was only 5V, which would be bad, but when I looked at some newer data sheets the HC parts have a Vcc range of 2 to 7 VDC, so if you used 3.3V it should be ok. However, I would use a class of parts that is more commonly known for 3.3V logic to make things more obvious, like LVTTL. Or you could use LVX, which is 3.3V with 5V tolerant inputs.

What did you decide to use?