Memory Test - Toshiba 710CDT Maintenance Manual

3.5

Memory Test

To execute the Memory Test, select 2 from the DIAGNOSTIC TEST menu, press Enter and
follow the directions as they are displayed on the screen. Move the highlight bar to the subtest
you want to execute and press Enter.
Subtest 01 Constant data (real mode)
This subtest writes a 256-byte unit of constant data to conventional memory (0
to 640 KB), then reads the new data and compares the result with the original
data. The constant data is FFFFh, AAAAh, 5555h, and 0000h.
Subtest 02 Address pattern data (real mode)
This subtest writes address pattern data created by the exclusive-ORing
(XORing) to the address segment and address offset in conventional memory
(program end to 640 KB), then reads the new data and compares the result with
the original data.
Subtest 03 Refresh (real mode)
This subtest writes a 256-byte unit of constant data to conventional memory (0
to 640 KB), then reads the new data and compares the result with the original
data.
The constant data is AAAAh and 5555h.
NOTE: There may be a short delay between write and read operations,
depending on the size of the data.
Subtest 04 Protected mode
NOTE: The CONFIG.SYS file must be configured without expanded memory
manager programs such as EMM386.EXE, EMM386.SYS or QEMM386.SYS.
Also, HIMEM.SYS must be deleted from the CONFIG.SYS file.
This subtest writes constant data and address data to extended memory (maxi-
mum address 100000h), then reads new data and compares the result with the
original data.
The constant data is FFh, AAh, 55h, and 00h.
710CDT/720CDT
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