ER-A450S (serv.man5). Service Manual - Sharp ECR Service Manual (repair manual). Page 36

The following check are performed for the optional RAM.

The following process is performed for memory addresses to be
checked. 

PASS1: memory data save

PASS2: Data "0000H" write

PASS3: Data "0000H" read and comparison, data "5555H" write

PASS4: Data "5555H" read and comparison, data "AAAAH" write

PASS5: Data "AAAAH" read and comparison

PASS6: Memory data restore

If a compare error is found in the check sequence from PASS1 to
PASS6, error print (error code E1) is performed. If there is no error
found to the end of the last address, the operation is completed
normally.
Then the following address check is performed. " " shows a valid
address, and "

✕

" shows an invalid address.

In case of an error, error code E2 is printed.

Check Address

JOB#201(ER-03RA)

200000H

|

200001H

|

200002H

|

200004H

|

200008H

|

200010H

|

200020H

|

200040H

|

200080H

|

200100H

|

200200H

|

200400H

|

200800H

|

201000H

|

202000H

|

204000H

|

208000H

|

210000H

|

220000H

|

240000H

|

260000H

|

Check the termination print. 

The test terminates after printing the termination printout. 
Termination print

E1---

200

(data check error)

E2---

200

(address check error)

200

(normal end)

: Error address

Loop back connector for D-SUB 9pin : UKOG-6705RCZZ

The program is activated by JOB#501 or JOB#550

SRV mode: 501 

 TL  : Channel 1

550 

 TL  : Channel 8

If the channel specified by JOB#CODE is not set, the machine per-
forms the mis-operation processing. When the channel is set, the
machine conducts the loop check concerning the channel specified
by JOB#CODE by using the loopback connector.

The following three items are checked:

Control signal check

Data transfer check

Timer check (RS-232 onboard timer)

Check 

Control signal check (ERn-DRn

•

CIn, RSn-CDn

•

CSn loop check)

OUTPUT

INPUT

ERn

RSn

DRn

CIn

CDn

CSn

OFF

OFF

OFF

OFF

OFF

OFF

OFF

ON

OFF

OFF

ON

ON

ON

OFF

ON

ON

OFF

OFF

ON

ON

ON

ON

ON

ON

The read check about the above INPUT items and interrupt check of
CS, CI and CD are performed.

Read check:

ER and RS are switched over in the order as
shown in the above table to confirm the logic of
DR, CI, CD and CS.If the read logic is different
from the one in the table, error print-outs occur.

Interrupt check: Allows the interruption of either of CS, CI and CD

one by one. (The mask is released.)
The interruption does not take place when each
signal is turned on. Or if the interruption occurs
when a signal is turned off, error print-outs occur.

Each of the above checks should be made in four cycles.

Check 

Data transfer check (SDn-RDn loop check)
In this check, transfer 256-byte loopback data of $00

∼

 $FF.

Note) The above check should be made with the baud rate set at

9600BPS.

Check 

Timer check
Before making check 

, set the corresponding timer at

10ms for RCVDT activation, and check to see that:

1) TRQ1 is not generated during the execution of  check

.

2) TRQ1 is generated in 10msec. after check 

  is    fin-

ished.

If an error occurs during the above checks, following error print-outs
occur. Even if an error occurs during check 

, the test is continued

after the corresponding error print-out has occurred, but if an error
occurs during the execution of check 

 or 

, the test is terminated

after the corresponding error print-out has occurred.
Note that when check 

, 

 or 

 terminates, the termination print-

2

0

7-SEGMENT DISPLAY:

0

SIGNAL NAME

CD

RD

SD

ER

GND

DR

RS

CS

CI

1

2

3

4

5

6

7

8

9

PIN No.

5 – 6