[comp.sys.transputer] Reset and error flag

davidb@inmos.co.uk (David Boreham) (10/11/90)

Kevin  (kevina@latcs1.oz) writes:

>	I have a question concerning the Transputer of which no answer
>has become obvious through either the data sheets or normal contact.
>The problem is: should the ERROROUT signal of any of the CPU's get reset
>                to an inactive state after a reset. (not analyse state)?
>                This is assuming that the CPU does not have an ERRORIN
>                input, or if it did then it is at a inactive state.


The state of the error flag is not affected by reset. Some devices tend
to power up with it set, others with it clear. Experience shows that 
about 80% of devices power up with error clear most of the time. This
leads some users to assume that error is cleared on reset. When they
encounter a device which powers up with error set sometimes, they get 
worried. 

I say again---Error is NOT affected by reset and should be treated as
a random variable  until a program has set or reset it.



David Boreham, INMOS Limited | mail(uk): davidb@inmos.co.uk or ukc!inmos!davidb
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