Real time clock interface / coding

[dtief]

Hi,

I am working on interfacing a BQ3285EP real time clock IC to a micromint 80C52 processor.

I have done a *lot* of projects with the 80C52 w/BASIC, all kinds of I/O.

Here's the problem:

I can verify that I can progam the control registers- I can tell because I can set the bits to activate the squarewave output.

I cannot read the registers for some reason. Not the control registers, not the time / date registers. The interface waveforms look ok with my logic analyzer. I am getting FF for any read of the registers.

Data sheet:
http://focus.ti.com/docs/prod/folders/p ... 3285e.html

This is for a home project, so I can't push TI tech support much...

Thank you,
Dave

[Steps Needed to Recreate Problem:

[dyarker]

Intel or Motorola mode?

[dtief]

Intel mode.