Service manual

Transputer Services Logic
Digital Service Manual
Issue 3 Page 7
TRANSPUTER
WRITE
LATCH
LCA
`DOWN' SERVICES
`UP' SERVICES
UpReset
UpAnalyse
UpError
Reset1
Analyse1
Error1
Reset2
Analyse2
Error2
Reset3
Analyse3
Error3
TRANSPUTER
EXTERNAL
MEMORY
BUS
Reset
Analyse
Error
Err1
Err2
Err3
On-card logic (external to the transputer itself) is used to drive `up' and `down' service
channels. Reset and Analyse signals flowing into the card propagate down to the sub-
systems beneath. Also the transputer is able to Reset or Analyse any of its children by
means of an addressable latch.
Error signals from children are presented to an LCA array which the host transputer
then monitors and if necessary, action is taken. Error signals also propagate up through
the 'up' service channel, notifying the card above of an error condition.