> No, I believe they are not.  What kind of circuit are you working
> with?  If the circuit is calling for pull-up resistors on the
> outputs and depending upon the load, you might be able to shoe-
> horn the 4050's into place and do away with some pull-up resistors
> at the same time.  The 4050 has about the same high voltage
> (inputs over Vcc) ratings as the 7407.
>
> michael brown

First off, thanks to everyone for the useful responses!  This list
is an invaluable resource for those of us new to the PIC.

I'm playing around with using a PIC as an AT Keyboard emulator.
Looking at Motorola's AN1723 app note ("Interfacing MC68HC05
Microcontrollers to the IBM AT Keyboard Interface"), page 17 states:

"The AT keyboard specification also calls for both the data and
clock lines to be open-collector signals so that the host can
interrupt a keyboard-to-host data transfer...Therefore, an open-
collector buffer device along with an accompanying pullup resistor
must be used as an interface between [the MCU] and the host keyboard
interface."

In the circuit described in the app note, they use a 7407 hex buffer.

Bill.

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