schimpf@utah-cs.UUCP (James Schimpf) (08/13/85)
Summary:Problem explained Expires: References: <120@mck-csc.UUCP> Sender:schimpf Reply-To: schimpf@utah-cs.UUCP (James schimpf) Followup-To: Distribution: net Organization: Univ of Utah CS Dept Keywords:80186,INTEL I had put out a previous article on the problems we were having a 80186. The timers which we were attempting to use as baud rate generators wouldn't work correctly. We had (we thought) done it all correctly. The timer input gates were tied high and the software set them for continuous run mode. The problem it turned out was RESET. Our RESET pulse was generated by a rather noisy push button and the very last bounce violated INTEL's timing specs on the RESET signal. It appears the timers are the last thing in the chip to be reset and if you don't have the pulse at least 4 clock pulses long the timers will do strange things. All the other parts of the chip worked (CPU, MMU, DMA...) but the timers require this long reset. --jim schimpf