K7 Rewind Tis; K8 Read/Write Memory Troubleshooter - HP 9845B/C CE Handbook

5-12 9845B/C
Diagnostics
k7 Rewind TIS
Pressing
(}L)
rewinds a tape cartridge installed in the right-hand cartridge drive (TIS).
k8 Read/Write Memory Troubleshooter
This test allows you to select specific memory tests. If the SHIFT LOCK key is down, the test will
not stop on an error.
More than one test can be selected. Here is a list of the available tests and the key to press to
select each test.
The
[j=:J ,
CD , CD
and
UJ
keys select different memory tests. Pressing the
CD
key enters the "peek and poke" portion of the memory troubleshooter program. Peek and
poke is described at the end of this test description.
Press Test
Marching Pattern - A test pattern is stored in memory. The first word
is read and verified and the complement of the test pattern is stored in
the first word. This sequence is continued for every word in the block
of memory. Once the pattern has been "walked up" memory, its
complement is walked down. The marching pattern test walks up and
down six different patterns. This test verifies that ones and zeros can
be stored in all memory cells, and checks for opens and shorts in data
bus lines.
Refresh - Zeros are stored in memory. The memory is left alone for
ten seconds and then verified. Ones are then stored in memory and
the sequence repeated. This test checks the refresh circuitry.
Byte - Zeros are stored in memory. Ones are then stored in the
right-byte using the byte operation. Memory is then verified. Zeros are
stored in memory and ones are stored in the left byte. Memory is
verified. The sequence is then repeated with ones stored in memory
and zeros stored in left and right bytes. This test checks memory byte
operations.
Walking bit (ones and zeros) - Every cell in a byte half block of
memory is set to zero. A one is written in the first cell, and all other
cells are read to verify that it is still one. The tested cell is then restored
to a zero and the next cell is set to a one. All cells are again read to
verify their contents. The sequence is continued for every cell in the
block. Its complementary pattern walking zeros completes the test.
Each 64k block is tested, 32k bytes at a time. This test checks for
memory cell row and column interactions. This test takes about six
hours to test each 64k byte block of memory.
Select the tests in the order you want them to run; then press ( CONTINUE). If no tests are speCified
all the tests will be run.
Enter the octal block address of the memory block to be tested and press
(CONTINUE).
If the
specified block is not present,
BLK
NOT PRESENT
is displayed. Press
(CONTINUE)
to enter
another block address. If no block address is entered, the default is to test all blocks of memory.
Press
C!:J
to test all blocks.