Transtech Transputer, User Manual

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TRAM checklist
186
Transputer Motherboard User Manual TMB M 711
12.1.1 Reset
Check the setting of the control configuration jumpers on the
motherboard. With the default settings given in this manual, sub-
system pins are not required.
Using a logic probe (with LEDs that light to show high or low TTL
signal states) check that the reset pulse can be seen. The pulse is
quite short, but should be clearly visible. Most voltmeters are too
heavily damped to show the reset pulse.
12.1.2 Links
Pipe-jumpers are a common source of trouble. Check that they are
fitted in the right places, and that the SIL strip between the TRAM
and the motherboard is fitted.
Check the settings of the link patch area, and cable connections.
Using a continuity tester or resistance meter, check the connection
of the link. There should be a 56 Ohm series resistance.
If a transputer cannot be booted from one link, even if the link is
correctly connected, it may be because its other links are not held
low, but are disconnected and floating high. All motherboards
incorporate pull-down resistors to prevent this.
12.1.3 Link speed
Check jumper settings. Check TRAM signals with a voltmeter or logic
probe - both link speed signals should be high for the default
20MBit/s operation.
12.1.4 Analyse
Check the TRAM analyse signal is low (not asserted). It should
remain low when
check
is run.
12.1.5 Power
Using a voltmeter, check that 5V is present.
12.1.6 Clock
Using an oscilloscope or logic probe, check that the 5MHz clock is
present.