3.10 Peripheral

3 Diagnostic Programs

3.9Communication (COMM)

Subtest 01

LPT

This test item is to check whether there is open or short circuit issue in the external pins by looping back the external pins, controlling the voltage of each data pin, control pin and status pin.

The test requires an external connector to insert into the tested LPT port. Below is the connector's description.

Fixture Description:

(9)+ PD7

(8)+ PD6

(7)+ PD5

(6)+ PD4

(5)+ PD3

(15)-ERROR

(14)-AUTFD

(16)-PINIT

(1)- STROBE

(10)- ACK

(4) + PD2

 

 

 

 

(12) + PE

 

 

 

 

(3) + PD1

 

 

 

 

(17) - SLIN

 

 

 

 

(2) +PD0

 

 

 

 

(11)+ BUSY

 

 

 

Note: (1)~(17)

--------

 

Pin number

PD0~ PD7

--------Data Line

Status Line --------

–ERROR(S3), +SELECT(S4), –ACK(S6), +PE(S5), +BUSY(S7)

Control Line--------

–AUTFD(C1), –PINIT(C2), -STROBE(C0), –SLIN(C3)

1. Register Check

 

 

 

 

 

Check whether the data register and control register works normally.

2. IRQ Check

Check whether LPT interrupt works normally.

3. External Loop back

Check whether there is open or short circuit issue.

4. ECP Mode

Satellite A100/A105 / TECRA A7 Maintenance Manual 59

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Toshiba PTA71, PTA70, PSAA9 manual Communication Comm, Peripheral Diagnostic Programs