Epson 10020 - Manual (Page 193)

Error Codes and Messages
This table lists all the error codes and messages that may appear
during diagnostics checks.
Error code Message
System board
101 8088 CPU ERROR
102 27128 ROM CHECKSUM ERROR
103 8254 TIMER COUNTER REGISTER ERROR
104 8254 TIMER COUNTER ERROR
105 8237 DMA CONTROLLER REGISTER ERROR
105 8237 DMA REFRESH ERROR
108 8048 SELF DIAGNOSTIC ERROR
109 8259 INTERRUPT CONTROLLER ERROR
111 146818 CMOS BATTERY ERROR
112 146818 CMOS CHECKSUM ERROR
113 8088 INSTRUCTION ERROR
Memory
201 MEMORY/PARlTY ERROR
Keyboard
301 8048 ERROR
302 NON-STANDARD OR DEFECTIVE KEYBOARD
Monochrome display adapter and CRT
401 V-RAM ERROR
402 VIDEO SIGNAL ALWAYS HIGH/LOW
403 ATTRIBUTE ERROR
404 CHARACTER SET ERROR
Color graphics adapter and CRT
501 V-RAM ERROR
503 ATTRIBUTE ERROR
504 CHARACTER SET ERROR
505 40-COLUMN CHARACTER SET ERROR
506 320x200 GRAPHICS MODE ERROR
507 640x200 GRAPHICS MODE ERROR
508 SCREEN PAGING ERROR
509 LIGHT PEN ERROR
510 COLOR VIDEO ERROR
D-36 Performing System Diagnostics