SEVERE Bug in mc68360 _ISR_Handler???

Chris Johns cjohns at
Tue Jul 17 12:43:14 UTC 2001

Thomas Doerfler wrote:
> So here we are. I hope I could make my ideas clear in this mail. Any
> hints welcome....

Interesting analysis. I am still looking over it.

FYI I tested this code by looping the RTS/CTS signal on a 68360 serial
port. The interrupt was on level 4. The CTS interrupt toggled the RTS
output. Checking the code, it looks like the PIT was at level 1. Hmmm I
wonder if the timer ever got a look in. I suspect it did not.

Also, Motorola fixed the '060 and Coldfire's by allowing the first
instruction after the interrupt to execute before allowing the core to
service another interrupt.

 Chris Johns, cjohns @

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