Table 6-2 68K Processor Power Up Self-Test Error Codes - Tektronix Phaser 340 Service Manual

6
Troubleshooting
6-4 Phaser 340 Color Printer
3. Observe the right LED; it represents tests on the main board's print
engine 68K processor. During power-up the LED flashes twice and
then stays lighted. It then blinks intermittently as the processor test
run. Like the 29K LED, if it blinks in a regular, repeated pattern, the
processor is looping on a failed test. After successful power-up, the
left LED blinks in a regular 2 beat-pause-2 beat-pause pattern. If the
LED repeatedly flashes in the same sequence then the 29K processor
has encountered an error and is looping. The possible LED-encoded
error codes are listed here:

Table 6-2 68K processor power up self-test error codes

Right LED flashes Meaning
Long flash =5
Short flash=1
3L+1S=16
1 CPU Interrupt
2 Instruction ROM: Data Bus
3 Instruction ROM: Checksum
4 SRAM: Validate data paths
5 SRAM: Byte-wide device-independent test
6 SRAM: Memory cell test
7 SRAM: Validate address paths
8 PE NVRAM: Validate data paths
9 PE NVRAM: Memory cell test
10 PE NVRAM: Validate data paths
11 MC ASIC: Read registers only
12 MC ASIC: Validate data paths
13 MC ASIC: Write/read registers
14 MC ASIC: FIFO validation
15 DMC ASIC: Validate data paths
16 DMC ASIC: Write/read registers
17 DMC ASIC: ROM validation
18 DMC ASIC: Validate RAM blocks
19 DMC ASIC: Timer registers and IRQ
20 DMC ASIC: IRQ validation using test mode
21 DMC ASIC: ADC conversion
22 IPC validation (joint test with 29K processor