Ram Diagnostics; Standard Ram Check; Up-P02Mb2 Check - Sharp ER-A770 Manual

ER-A770 Diagnostics V 1.0A
Product & Test Diagnostics

RAM Diagnostics

ROM & SSP Diagnostics
Clock & Keyboard & Clerk Diagnostics
Serial I/O Diagnostics
LCD Diagnostics
Rear & Pole Display Diagnostics
SRN Diagnostics
EFT Diagnostics
MCR Diagnostics
Drawer Diagnostics
Diagnostics End
"Product & Test Diagnostics" is used only in the production
process, and must be not used in servicing.
3-2. RAM Diagnostics
This diagnostics is used to test the standard RAM and the expansion
RAM.
The following menu is displayed. The cursor position is highlighted.
Use key and key to move the cursor. Move the cursor to the
process you desire and press the enter key. The selected individual
diagnostics program is executed.
RAM Diagnostics

Standard RAM Check

UP-P02MB2 Check

1) Standard RAM Check
Check content
For the pseudo SRAM of the standard RAM 1MB, the following
check is performed. The memory contents will not be changed by
this check.
The following processes are performed for the memory address
(700000H ~ 7FFFFFH) to be checked.
PASS1: Memory data save
PASS2: Data "0000H" write
PASS3: Data "0000H" read/compare, data "5555H" write
PASS4: Data "5555H" read/compare, data "AAAAH" write
PASS5: Data "AAAAH" read/compare
PASS6: Memory data writed the saved data
In case of a compare error in the check sequences of PASS1 ~
PASS6, an error display is made. If there is no error at all, the
check is normally terminated.
In addition, the following address check is performed.
In case of an error, an error display is made and read/write of the
address where the error occurred is repeated.
Check point address = 700000H, 700001H
700002H, 700004H
700008H, 700010H
700020H, 700040H
700080H, 700100H
700200H, 700400H
700800H, 701000H
702000H, 704000H
708000H, 710000H
720000H, 740000H
780000H
Display
The screen displays the capacity of RAM in the unit of 64 KB.
Standard RAM Check
Standard memory size : 1024KB PASS!!(or ERROR!!)
Error Address xxxxxxH
Write Data xxxxH
Read Data xxxxH
The error address and the bit are displayed only when the error
occurs. (If the error does not occur, they are not displayed.)
Terminating procedure
After completion of check, press the CANCEL key.
2) UP-P02MB2 Check
Check content
The UP-P02MB2 presence check is performed in the following
procedure. The memory contents must not be changed by this
check.
55AAH is written into 9FFFFEH.
9FFFFEH is read and compared with 55AAH. If the both data
are correct, the following procedure is performed. The system
reads 9FFFFEH and compares it with 55AAH. If both data are
correct, the following tests will be performed. If not, the screen
displays the message "Extended RAM size : 0KB", and ends
the test.
For the UP-P02MB2, the following check is performed.
The following processes are performed for the check address
(800000H ~ 9FFFFFH).
PASS1: Memory data save
PASS2: Data "0000H" write
PASS3: Data "0000H" read/compare, data "5555H" write
PASS4: Data "5555H" read/compare, data "AAAAH" write
PASS5: Data "AAAAH" read/compare
PASS6: Memory data writed the saved data
In case of a compare error in the check sequences of PASS1 ~
PASS6, an error display is made. If there is no error at all, the
check is normally terminated.
In addition, the following address check is performed in the above
check sequence.
In case of an error, an error display is made and read/write of the
address where the error occurred is repeated without performing
the check.