IBM System 23 Diagnostic User Guide
The IBM System/23 Diagnostic User Guide (Diagnostic User Guide 0001, "System/23 with Diskette"), part number 6841631, is the customer-engineer guide to the diagnostic programs of the IBM System/23 Datamaster. The title page lists its engineering-change history: EC 994445 (13 August 1981), EC 323398 (22 February 1982) and EC 327594 (5 April 1982); this copy is at EC 327594. Copyright IBM 1981. The PDF has 176 pages.
It describes the ROS-resident tests that run in the machine itself and the diskette-resident programs loaded from the CE diagnostic diskette. It is one part of the maintenance library: it refers to the service manual ("SM") sections and MAPs by number, for example SM 1230 for the latch probe pins and CE jumpers, and MAP 1100 for the probe set-up.
Contents
[edit | edit source]Page numbers are the guide's own.
| Section | Page |
|---|---|
| 1-12. Introduction and test sequence; ROS-resident programs (power-on diagnostic PID 1200, diskette drive test PID 1500); diskette-resident programs (DCP, FLT programs, CE utilities) and program rules; MAP organisation; service manuals; cross-references; error log; TRAP data; intermittent error procedure; special tools; program operation summary chart | 1-19 |
| 13. PID 0001 Diagnostic Control Program (DCP) | 21 |
| 14-20. CE utilities: PID 0100 format diskette, 0105 copy diskette, 0110 read verify (including a head alignment check), 0115 VTOC display, 0120 error log display, 0125 EC/PTF support, 0150 configuration display | 26-74 |
| 21. PID 1200 processor power-on test | 75 |
| 22-24. PID 1205 CPU processor FLT, 1210 CPU storage FLT, 1212 update storage test | 88-101 |
| 25-27. PID 1300 keyboard FLT, 1400 screen image test patterns, 1450 word processing support test | 104-110 |
| 28-30. PID 1500 ROS-resident diskette drive 1-4 test; PID 1505 and 1510 diskette FLT parts 1 and 2 | 115-132 |
| 31. PID 2300 5241/5242 printer FLT | 139 |
| 32. PID DMON ROS-resident monitor | 154 |
The power-on test (PID 1200)
[edit | edit source]From section 21 (pp. 75-76):
- PID 1200 is stored in ROS and runs at every power-on, or whenever program flow branches to location 0000. It takes 25 to 35 seconds depending on configuration.
- Before the CRT is started (routines 01 to 06), an error stops the machine and leaves an error code in a set of hardware latches, which the customer engineer probes (SM 1230, MAP 1100). After the CRT is started, the latch contents are shown on the screen, and the display attribute of each routine gives its result:
| Display | Meaning |
|---|---|
| Normal | The routine ran without error. |
| Flashing reverse video | Error in a part critical to system operation; the system stops after the power-on sequence ends. |
| Reverse video | Error in a part that is not critical; pressing ERROR RESET lets initialisation continue. |
| Underline | The feature this routine tests is not fitted. |
- If a TRAP occurs during power-on testing, the failure is in the routine after the last one displayed.
- Two CE jumpers on the CPU board (located in SM 1230) set the options. With the loop jumper the test repeats until the jumper is removed; disconnect any external diskette attachment cable first. With the stop-on-error jumper the system stops once the failure indicator is displayed. IBM recommends fitting the stop-on-error jumper whenever the loop jumper is fitted and the machine is left unattended.
- The diskette drive test (PID 1500) is started after the power-on test completes by pressing CMD/TEST and then CMD/ERROR RESET, and the drive (1 to 4) and options are chosen on the numeric keypad; key 9 ends it (section 12, p. 19).
What this guide does not contain
[edit | edit source]It describes the diagnostics only. Locations, jumper positions, voltages, removal procedures and parts are in the service manual sections and MAPs it cites; see the IBM 5322 Computer Service Manual. There are no schematics or component values.
Download: IBM System 23 Diagnostic User Guide 6841631.pdf