Sony KDS-R50XBR1 Training Manual page 71

4. Protection Circuits
condition or for the presents of any DC voltage level. If either of these
conditions is detected the protection alerts the DE microprocessor of the
failure and a 7X flash pattern on the Standby/Power LED will occur.
Panel Error or Device Acknowledgement Error (9X Power/
Standby Red LED Flash Pattern)
This DE microprocessor monitors the I2C communications between
itself and the C-Board, S1-Board, and S2-Board. This protection
circuit will trigger if the previously mention devices do not send an
acknowledgement (over the I2C bus) during initial TV power-up, or if the
I2C bus communications between these devices is interrupted during
normal operation. In either case, the DE microprocessor detects the
failure, the TV will shutdown, and the Red Power/Standby LED flashes a
9X flash pattern.
TVP-21 68