In-Reply-To: <4.3.1.2.20000517171853.00a79180@192.168.0.100>

David Duffy <piclist@AUDIOVISUALDEVICES.COM.AU> wrote:
> Hi All,
> This is my 1st time using 3v3 devices (ISD5008 voice chip) and was
> wondering about the best way to interface the PIC to it. (5v supply)

Use an open drain output type idea.

When you have an output from the PIC (5V) to the voice chip (3V) put a
pull up resistor to 3V and instead of driving the output high for logic
one just set it to high impedance with the TRIS register.

The other way round an output from the voice chip into a PIC input
should work as is because the PIC will take 3V as logic one anyway.

Brian Gregory.
briang@cix.co.uk