Question on 3v to 5v SPI

[BertMan]

Thanks Sean. I will look into the 74LVC07A. If the Pic will accept a 3v input as a high, then half my battle is over! But here is what I was originally suggesting.... Does this look correct?

[sean-h]

Not sure if that looks correct with the tranny, would pop a resistor in on the base to start with and is the emitter going to gnd on the chip and your 5v is the load output coming off it?

Heres a good link to help you choose the config if using a tranny you need but remember that using a tranny will invert the signal and to allow this in your code.

http://www.kpsec.freeuk.com/trancirc.htm

Regards

Sean.

[BertMan]

Actually I am using a transistor basically as a 3v switch in this schematic. When the compass sends a 3v signal to the base, the 5v on the collector would flow to emitter, thus sending a 5v pulse through the emitter to the 5v input on the pic. Er, in theory.

[BertMan]

I found an excellent pdf that expains different ways to mix 3v and 5v logic and gives part #'s too. Just in case someone else is trying this... http://www.freescale.com/files/micro...ote/AN2433.pdf