Post by thread:7 bit clock SPI problem on 16C74

Hi all, I have interfaced a Burr-Brown A/D (ADS1213) to a 16C74 via SPI (master mode). Sometimes the communication hangs and I could see on the oscilloscope that the problem is due to a wrong clock issued by the 16C74 SPI. Every time the communication hangs I can see a 7 bit clock instead of the normal 8 bit clock. I use the SPI with clock = TMR2/2 at 9765.625 Hz. Anyone experienced something similar before? Thanks in advance, Raffaele Raffaele Rialdi Vevy Europe Advanced Technologies Division email spam_OUTraffaelerTakeThisOuTvevy.com

Solved. Hope can be of help in the archives. To avoid this problem, you have reset (clrf TMR2) just before sending/receiving data. In fact if TMR2 is very close to resetting, you could have a very short clock (200ns at 20MHz clock) that would cause a 'de facto' 7 bit communication. Regards, Raffaele {Original Message removed}