Acorn FileStore Troubleshooting Guide
Fault finding for the Acorn FileStore E01 and E01S base units and the E20, E40S and E60S hard disc units follows Acorn's FileStore Service Manual (0482,001): watch the power-up sequence, check the printer line feed, check the network link, measure the supplies, and finish with the dealer test suite.[1] Disassembly, the backup cell and the capacitor list are in the Acorn FileStore Maintenance Guide.
Warning: the supply and mains switch carry mains voltage with the cover off. Make the mains connection last and remove it first.[1]
Power-up sequence
[edit | edit source]A working base unit, with any hard disc units attached, starts like this:[1]
- The power and mode lights come on.
- Each hard disc unit spins up (a rising hum; about 10 seconds for the E20, a few seconds for the E40S and E60S) and its drive light flickers as it is accessed in turn.
- The floppy drive light on the base unit comes on.
- All lights go out except the power lights. The FileStore is ready in network mode.
If the sequence does not complete, the unit is faulty. With the front flap open at power-up the unit starts in maintenance mode instead, and the mode light stays on.[1][2]
| Symptom | Probable cause | Action |
|---|---|---|
| No lights, fan silent | Mains lead, plug fuse (3 A on the E01, 5 A on the E01S) or rear switch; supply failure | Check the plug fuse and switch; measure the supply outputs (below)[1] |
| Hard disc unit does not spin up | Supply or connections in the hard disc unit | Check the supply and its connectors in that unit[1] |
| Starts in maintenance mode every time | Flap not closed, or the optical flap sensor not seeing the flap | Close the flap; check the opto sensor and its lead to the board[1] |
| Configuration lost after power-off | Backup cell flat or failed | See the backup battery section of the maintenance guide[1] |
Stage 1: initialisation
[edit | edit source]Connect a printer to the FileStore and switch it on. Open the access flap and switch the FileStore on while watching the printer. A line feed means the processor has started and run the firmware; go to stage 2.[1] If there is no line feed, check with an oscilloscope:
| Signal | E01 | E01S | Expected |
|---|---|---|---|
| Processor clock | IC3 pins 3 and 39 | IC16 pins 3 and 39 | 2 MHz, from the 8 MHz crystal X2 divided by four |
| NMI | IC3 pin 6 | IC16 pin 6 | High |
| Real-time clock | TP1 at IC2 | TP1 at IC1 | Printed as "1024 kHz"; the clock crystal X1 is 32.768 kHz |
| Address and data lines | At IC3 | At IC16 | Activity |
The E01 power-on reset is IC24 with D6, R9 and C6, which hold the reset line low while the 5 V rail settles.[1] On the E01S, C13 charges through R45 and D7 at power-on while the latch IC6 keeps the EPROM IC7 enabled for the copy into RAM.[1] A unit that never starts, with the clock present, points to these circuits, the EPROMs or the RAM. Reseat the socketed EPROMs; on the E01 the processor, both EPROMs, the floppy controller, the VIA, the RTC and several logic ICs are socketed.[1]
Stage 2: network link
[edit | edit source]| Symptom | Probable cause | Action |
|---|---|---|
| Stations cannot see the FileStore | Econet module faulty | Replace the module (plugs into SK10 and SK11)[1] |
| No clock | Clock path or clock enable | Check the clock path and enable. On the E01 the clock comes from IC16 and IC28 through the line driver IC26, controlled from IC21 pin 19 (CB2)[1] |
| Line jammed | Data pair held | Check for about 0.3 V across the data pair[1] |
The board's own clock and active terminator switch in when the processor sees no network clock at power-up or after a transmission error. The terminator puts about 0.2 V across the data pair.[1] Links on the board select the clock period and divide ratio; Acorn gives 200 kHz as the optimum setting.[1] A FileStore will run a network of itself and one station, which makes a quick bench test with a single computer fitted with an Econet interface.[2]
Power supply checks
[edit | edit source]Make the measurements with every connector in place. To measure current, break into the red (+5 V) or orange (+12 V) lead with the power off, then switch on; currents change in the first seconds after power-up.[1]
| Unit | Rail (lead colour) | Limits | Expected current |
|---|---|---|---|
| E01S board | +5 V (red to black) | 5.0 to 5.25 V | 0.9 to 1.2 A, 1.5 A maximum; falls by about 100 mA after the EPROM has been copied to RAM |
| E01S drive connector | +5 V | 5.0 to 5.25 V | Per drive: 50 mA standby, 275 mA reading or writing |
| E01S drive connector | +12 V | 11.4 to 12.6 V | Per drive: 500 mA motor start, 140 mA seek, 90 mA reading or writing |
| E20 | +5 V (red) | 4.9 to 5.2 V | Hard disc about 1 to 1.5 A; host adaptor about 500 mA |
| E20 | +12 V (orange) | 11.4 to 12.6 V | Hard disc up to 4.5 A, falling to about 2 A at speed |
| E40S, E60S | +5 V (red) | 4.9 to 5.2 V | 0.7 to 1 A |
| E40S, E60S | +12 V (orange) | 11.4 to 12.6 V | Up to 2.5 A, falling to 0.4 to 0.9 A within about two seconds |
For the E01S board current, fit the Econet module, disconnect the SCSI bus from other units but leave the terminator on, and close the flap. The floppy drive power plug carries, in order, +5 V, 0 V, 0 V and +12 V. Acorn measured drive currents with a small break-out board in the lead; avoid shorting it against the drive tops or the supply board.[1]
The supplies are exchange assemblies in Acorn's lists, with no circuit published.[1] A supply that fails these limits needs component-level work on the supply itself or a replacement; see Capacitor Failure Symptoms.
Hard disc units
[edit | edit source]| Symptom | Probable cause | Action |
|---|---|---|
| Disc does not spin up | Supply or connections | Check the supply rails and current above[1] |
| Disc spins, base unit does not find it | Address decoding or SEL/BSY handshake on the expansion bus | Run the SCSI interface tests in FServTest[1] |
| Bus lines stuck | With the bus free, every line should float to its terminating resistors: D0 to D7 and A0 to A7 at 2.5 V | A line at +5 V or 0 V indicates a short; D0 to D7 all at 0 V, or a mix of 0 V and 2.5 V, usually means a buffer is enabled[1] |
| Faults appear when a second device is chained through an E20 | Double termination | Remove and keep resistor packs RP2 to RP4 on the E20 host adaptor[1] |
Acorn's error code list gives Winchester error numbers with a key to the likely cause: cables, host adaptor, controller, drive or supply. For example, 04 "Drive not ready" points to the cables between the controller and the host.[3]
Lost passwords and system user
[edit | edit source]Acorn's December 1987 engineering newsletter gives a recovery for a FileStore whose password file is deleted or overwritten. It relies on maintenance mode (start the E01 with the flap down) and the system user, whose identifier starts as SYST. Format a blank disc in the left drive in maintenance mode, restart in user mode without the E20 powered, log on as SYST with no password, create a new privileged user, then restart with the E20, rename or delete the damaged PASSWORDS object and copy the new password file onto the server disc. If the mode light flashes quickly when restarting with the E20, the method will not work and the hard disc has to be reformatted.[4] Acorn's error list gives the same advice for error &21: use a floppy that has a password file on it.[3]
Final checks
[edit | edit source]If the stages above find nothing, run Acorn's dealer test suite from a Master 128 through an Econet Test Box: all the FServTest tests, then FServFmt and FServInit on each disc, then FServSoak with every test pattern. Formatting and initialising erase the discs, so archive the data first.[1]
Older units may still carry the original ROMs. Acorn's field change orders replaced the E01's IC4 and IC5 with EPROMs 0254,204-03 and 0254,205-04, and the E01S's IC7 with 0282,008-01.[2]
Related pages
[edit | edit source]- Acorn FileStore
- Acorn FileStore Maintenance Guide
- Hard Drive Maintenance and Repair
- Floppy Drive Repair
References
[edit | edit source]- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 1.18 1.19 1.20 1.21 1.22 1.23 1.24 Acorn Computers, FileStore Service Manual, part no. 0482,001, issue 1, 21 September 1989 (retyped edition). Hosted on this wiki: Acorn FileStore Documentation. E01 timing, Econet clock and active terminator pp. 17 to 19; E01 memory map and CMOS allocation pp. 21 to 23; E01 link survey p. 24; E01 fault finding pp. 25 to 26; E20 fault finding pp. 47 to 48; E01S fault finding pp. 77 to 80; E40S/E60S fault finding pp. 99 to 101; appendix A test equipment pp. 103 to 113.
- ↑ 2.0 2.1 2.2 Acorn Computers Customer Services, Customer Service News, February 1989, appendices FCO 2005 (E01, replacement EPROMs 0254,204-03 in IC4 and 0254,205-04 in IC5) and FCO 2006 (E01S, replacement EPROM 0282,008-01 in IC7), including the post-upgrade test: switch on with the flap down and check that the mode light stays on, close the flap and check for user mode, then connect a computer with an Econet interface, the FileStore providing the clock. archive.org scan (retrieved 2026-10-02).
- ↑ 3.0 3.1 Acorn Computers, Econet Level II, III and FileStore Error Codes, 12 pp. Hosted on this wiki: Acorn FileStore Documentation. File server errors with area and fix (including &21 "Cannot find Password file", with the advice for FileStore to use a floppy with a password file on it, and &36 "Invalid window address"); Winchester error codes with a key to causes 1 to 8.
- ↑ Acorn Computers, Acorn Engineering News issue 2, document 999,0031, December 1987, pp. 4 to 5: "FileStore Service" (central service at RCS for the E01 and E20; the circuit is based on a 65C102 with two ROMs and 64K of RAM; E01 circuit diagram enclosed) and "Econet" (password file recovery using maintenance mode and the SYST identifier). Chris's Acorns copy (retrieved 2026-10-02).