Service / Test Mode - Sony DVP-NS300 Training Manual

Service mode testing consists of the following:
1. Initial Communications
2. Entering the Test Mode
3. Contents of the Test Mode
Initial Communications
Initial communications must occur before the unit remains ON and the test mode can be accessed. Therefore,
if the unit does not power up, you must confirm the communications between a pair of ICs. The flow chart in
Figure 7-1 helps you do this.
This process will determine if the data in the slave IC can be accessed, read and written.
If communications fail, error codes will be out put. Each error code identifies error type and IC stage where it
occurred.
# Different
Process of
In the above address
Writing the
data
Chapter 7 - Service / Test Mode
How does the test mode operate?
Activate Main
IC as Master
Select a
SLAVE IC
Access selected
Address locations of
Slave IC
Read the current
Data and save
Write specific data
FIGURE 7-1 - DEAD SET / NO INITIAL COMMUNICATIONS
Read the data in
the same
locations
Verify WRITE & READ
Data.
WRITE &
READ data
Same?
Yes
Error not
detected
32

7. Service / Test Mode

No
Error code
displayed