abi SYSTEM 8 - Page 23

Page 23
EXERCISE 28 : MEMORY
ACTION
Attach a 40 way clip to the 64 - Way ribbon cable. Connect cable to BFL and clip to U12
EPROM.
Note the SETUP and press START on the IC tester. Attach BDO LOW to TP84 DIS CLK
stopping counter U15. Attach BDO HIGH to TP88 DIS_DATA_BUF stopping U17 from
outputting on the bus. Note if you wish to do the full 10 minute test got to SETUP and select
Truth Table. Then press START on the IC tester.
EXERCISE 29 : MEMORY (II)
ACTIONS
Note Clip is attached to U12 EPROM.
BDO LOW is still connected to TP84.
BDO HIGH is still connected to TP88.
Remove jumper J3 to stop the link between pin 26 and 23 of U12.
Note VERIFIER settings
- In circuit
- Training PCB
- 256k by 8
- Checksum C52D
Press VERIFY button. Note the Checksum result window Verifies OK.
EXERCISE 30 : LIVE COMPARISON
ACTION
Add your own live comparison test here on the 74LS244 X2 (U13 and U17)
DESCRIPTION
The Live Comparison feature needs two BFL modules to be fitted in the system (128
Channels). Two boards of the same type are needed and all connections are duplicated for
each module. Setup and test are the same as an individual test or a test in TestFlow.
The Test tolerance can be adjusted in the SETUP window. The Good module should be
connected to the upper of the modules or the secondary module if fitted differently.
COMMENTS
This is the optimum way to diagnose faults as you have the Good PCB at hand to try different
tests on. With a TestFlow you only get what you have saved to work with so if you want to
go more in depth you do not have a Master result to rely on.