Usually the Stamp levels will successfully drive a CMOS chip INPUT. If the CMOS chip is operating at 12 volts then you must be careful if you expect the Stamp to use that as in input. A 22K resistor in series with the input would probable protect the Stamp input.
Note that the newer CMOS chips will operate quite nicely at 5 volts so the foregoing is not an issue. Check the specs of the chip you want to use.
Comments
Note that the newer CMOS chips will operate quite nicely at 5 volts so the foregoing is not an issue. Check the specs of the chip you want to use.