Packard 386 SBC board
This is the processor board from a Packard 500TR flow scintillation analyser. My board came from the unit in DextersTechLab's teardown video.
It's essentially an ISA-bus 386 PC on an ISA card.
Part numbers on the PCB:
- 7101196
- 5091196-G
- 1310067 REV A (on PAL chip)
- 1310068 REV E (on BIOS chip)
Features:
- 80386SX processor, 16 MHz (chip rated at 25 MHz)
- 8x 30-pin SIMM slots (2x 512K modules fitted for a total of 1MB RAM)
- Chips & Technologies 82C836 “SCATsx” chipset
- Chips & Technologies 82C710 Super I/O
- 1x IDE channel
- 1x floppy drive port
- PS/2 mouse port
- Chips & Technologies 8042 keyboard controller
- Standard pinout
- Keyboard port, Keylock (keyboard inhibit), A20 line
- Chips & Technologies BIOS
Backup battery
The standard backup battery is a 3.6V lithium thionyl chloride cell.
Unfortunately a 3V coin cell is not suitable: the board has a very high discharge current. Three AA NiMH or alkaline cells may be a better replacement.
Connectors and jumpers
J1 - Watchdog
3-pin 0.1in-pitch header
Pins from left to right, with the RAM slots held at the left.
| 1 | 2 | 3 |
|---|---|---|
| notch |
| 1 | |
|---|---|
| 2 | MAX891 pin 11 (Watchdog In) |
| 3 | 0V |
This is likely a reset switch input.
J2 - PS/2 Mouse
5-pin 0.1in-pitch header
Pins from left to right, with the RAM slots held at the left.
| 1 | 2 | 3 | 4 | 5 |
|---|---|---|---|---|
| notch | ||||
| 1 | Mouse Data (82C710 pin 61) |
|---|---|
| 2 | |
| 3 | 0V |
| 4 | 5V via fuse |
| 5 | Mouse Clock (82C710 pin 60) |
J3 - Keyboard
10-pin IDC connector
Pins from left to right, with the RAM slots held at the left.
| 1 | 3 | 5 | 7 | 9 |
|---|---|---|---|---|
| 2 | 4 | 6 | 8 | 10 |
| notch | ||||
| 1 | Keyboard Data |
|---|---|
| 2 | Keyboard Clock |
| 3 | 0V |
| 4 | |
| 5 | 5V |
| 6 | |
| 7 | |
| 8 | |
| 9 | |
| 10 |
J4 - Front Panel
Mounted flat to the PCB. 8-pin (4×2) 0.1in-pitch Dupont connector.
Pins from left to right, with the RAM slots held at the left.
| PCB | |||
|---|---|---|---|
| 1 | 3 | 5 | 7 |
| 2 | 4 | 6 | 8 |
| 1 | Power LED + – via 150R to +5V |
|---|---|
| 2 | Power LED - – to 0V |
| 3 | Keylock switch 0V |
| 4 | Keylock, connect to 0V to lock – to 8042 pin 34 |
| 5 | Hard drive LED + – via 200R to +5V |
| 6 | Hard drive LED - |
| 7 | PC Speaker – via fuse to +5V |
| 8 | PC Speaker – via 33R to drive circuit |
Jumpers
- JMP1: (Unknown) - Connects to 8042 pin 33. Display Type jumper?
- JMP2: (Unknown) - normally set right. Sets centre pin to either 0V or 5V
- JMP3: Not fitted
- JMP4: 4-pin, unknown function
- JMP5: Not fitted
- JMP6: (Unknown) - normally set right.
- JMP7: CMOS Clear. Up (2-3) to clear CMOS. Down (1-2) for normal operation