Mike's PCjr Page

Does anyone know what components of the Speech Attachment are likely to have failed to give Error J at POST?

I haven’t personally troubleshooted any speech adapters but have heard that the 8255 PPI is a common point of failure. A bad 8254 timer could also cause error J.

The technical reference manual for the speech attachment includes schematic diagrams and a BIOS listing.

From the BIOS listing in the TR:

Code: Select all

POWER ON SELF TEST

DESCRIPTION:
      TIMER CHANNELS ON THE 8254 ARE TESTED FOR STUCK BITS.
      TIMER 1'S RESPONSE TO TIMER 0 IS CHECKED.
      HARDWARE ON THE CARD IS RESET (SEE BIOS RESET COMMAND)

ERROR CODES:  (SOME MAY BE PASSED BY CODE PREVIOUSLY EXECUTED
              FROM RAM)
      CUSTOMER LEVEL: J
      SERVICE LEVEL:  28XX
                        XX = 01 PORT A FAIL MODE 83H
                             02   "  B  "    "    "
                             03   "  C  "    "    "
                             04   "  A  "    "   81H
                             05   "  C  "    "    "
                             
                             10 STUCK BIT IN TIMER CHANNEL 0
                             11 STUCK BIT IN TIMER CHANNEL 1
                             12 STUCK BIT IN TIMER CHANNEL 2
                             13 CVSD FRAME NOT CHANGING
                             14 CVSD CLOCK NOT CHANGING
                             15 CVSD FRAME NOT RESPONDING TO
                                   CVSD CLOCK AS EXPECTED
                             23 ACL ERROR DURRING CARD RESET
                             26 TIMEOUT WAITING FOR  LPC
                                  COMPLETION DURRING CARD
                                  RESET

       PORT A = FB98H
       PORT B = FB99H
       PORT C = FB9AH

If you have a Hardware Maintenance and Service manual for the PCjr, get the service plug that came with it and plug it into the joystick ports. Then boot the machine and note the service code that replaces error J. Look up the code in the BIOS comment above to help pinpoint the problem.

Thank you. Finally got around to getting it fixed, and it was indeed the PPI that failed.

OK. Seems having the Speech Attachment and jrIDE connected at the same time is causing problems. I'm unable to boot to DOS from the jrIDE, and the text for when the jrIDE lists the Compact Flash card info is garbled. If I don't have the Speech Attachment connected, everything works fine. The RTC interrupt is disabled, so it can't be that.

Does the Speech Attachment just not play nice with the jrIDE, or could a bad connection on the 8255 be causing problems?

I use the two together without a problem. My sidecars (starting from the main unit) are Power, Speech, LPT1, LPT2, then jrIDE.