Tektronix RTD 710A Service Manual page 168

Number Level Loop AIM Description
20400 - Backup Battery Test
20400 2 Ls A Backup Battery Test.
Operation: Runs test 20401.
20401 1,2 LS A Battery Test.
Operation: Tesis both batteries for sufficient voit-
age by reading two battery check bits.
Tesis Battery Check iCs (A52U330, U170, and
U340).
20500 - Nonvolatile Memory Tests
20500 2 LS A Nonvolatile Memory (NVM) Test.
Operation: Norie.
20501 1,2 LS M Check Sum Test of NVM.
Operation: Verifies that panel setup NVM hasn't
changed since power down. When the instrument
is powered down, current front panel settings are
saved setting the NVM checksum. When the in-
strument is next powered up, it resets the front-
panel settings to those that existed at power
down. If the instrument is placed in the Level 2
diagnostics mode and this test executed, it
should pass.
If the instrument is placed in normal operation
and has one front panel setting changed, then it
is returned to Level 2 diagnostics and this diag-
nostic run, and error code £20501 should occur.
Also, if this test is run again after running 20502,
an error code E20501 should occur.
Devices tested:
NVM (A52U360 & U370)
Address Buffer (A52U335A, U355A, & U140)
Data Bus Buffer (A52U340 & U350)
Address Decoder (A50U250A & U240)
Chip Select (AS2U180D, U280D, US20A, Q322).
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