Amiga 1200
 | |
| Amiga 1200 | |
| Specifications | |
|---|---|
| Manufacturer | Commodore; later Escom |
| Type | Home computer |
| Released | 21 October 1992[1] |
| Intro price | £399 (UK)[1] |
| CPU | Motorola 68EC020, 14.18 MHz (PAL) or 14.32 MHz (NTSC)[1] |
| Memory | 2 MB chip RAM[1] |
| Storage | Internal 3.5-inch floppy drive; internal 2.5-inch IDE interface[1] |
| Display | — |
| Sound | 8364 Paula[2] |
| Graphics | AGA: 8374 Alice, 4203 Lisa[2] |
| ROM | 512 KB; Kickstart 3.0 (39.106), Kickstart 3.1 on Escom machines[1] |
| Ports / interface | PCMCIA Type II, 150-pin trapdoor expansion, clock port, IDE, serial, parallel, external floppy, two mouse and game ports, RGB, composite, RF, stereo audio[1] |
| Power | External supply 391029, 3.0 A at +5 V[3] |
| OS / Firmware | — |
| Predecessor | Amiga 600 |
The Amiga 1200 (A1200) is a home computer that Commodore launched on 21 October 1992 at £399 in the UK.[1] It uses the AGA chip set and a 68EC020 processor, with 2 MB of chip RAM, a 512 KB Kickstart ROM, a PCMCIA slot, an internal IDE interface for 2.5-inch drives and a 150-pin trapdoor expansion slot.[1] After Commodore's bankruptcy Escom built more A1200s; these shipped with Kickstart 3.1.[1] Like the Amiga 600, the A1200 uses surface-mount electrolytic capacitors that now leak; see the Amiga 1200 Capacitor Replacement Guide.
Main board
[edit | edit source]| Ref | Part |
|---|---|
| U2 | 8374 Alice (AGA Agnus) |
| U3 | 8364 Paula |
| U4 | 4203 Lisa (AGA Denise) |
| U5 | Gayle (F023A) |
| U6 | ROM 512K × 16, 150 ns |
| U7, U8 | 8520 CIA |
| U12 | Sony CXA1145 video encoder |
| U13 | 68HC05 keyboard microcontroller |
| U15 | LF347 or TL084 op-amp |
| U16, U17 | DRAM 256K × 16, 80 ns (U18 and U19 optional) |
| U20 | Budgie |
| U28, U29 | 1488 line driver, 1489 line receiver |
| U30 | BT101 triple 8-bit video DAC |
| U49 | PST518 low-voltage sense IC |
Commodore's table lists U1 as a "68000 processor 16MHz"; the production machine has a 68EC020.[2][1] The schematic marks the real-time clock as optional.[2] The Big Book of Amiga Hardware lists no battery-backed clock, and the WAIT 6502 blog knows of no board revision with one fitted; a clock comes from an expansion card instead.[4][5]
Board revisions
[edit | edit source]The Big Book of Amiga Hardware lists Rev. 0, 1, 1A, 1B, 1D.1, 1D.3, 1D.4 and 2B.[4] Changes it records:
- Rev. 1D.3: the first Budgie revision (-01); E123C and E125C removed from the board.
- Rev. 1D.4: Budgie -02; the 470 Ω resistor XR358 removed and a 470 Ω resistor added to pin 43 of Alice.
- Rev. 2B: either Budgie revision; R118 changed from 470 Ω to 220 Ω.
The Amiga Resource adds that Rev. 1A takes its chip RAM as 256K × 16 chips and Rev. 2B as 512K × 8 chips, and that on Rev. 2B the +12 V is missing from the RGB port, so genlocks need their own supply.[6] Escom-era boards seen by one collector were Rev. 1D.4.[7]
Power supply
[edit | edit source]The A1200 uses the same external supply as the A600, rated 3.0 A at +5 V, 0.5 A at +12 V and 0.1 A at −12 V, 22.2 W in all.[3] Wikipedia calls it "rather limited" at 23 W and notes that hard disks and even external floppy drives can stress it.[1] Ian Stedman measured an A1200 with a 68060 accelerator, two hard drives and a SCSI card drawing 3.0 A on +5 V, the supply's full rating.[8]
Repair and maintenance
[edit | edit source]- Amiga 1200 Maintenance Guide
- Amiga 1200 Troubleshooting Guide
- Amiga 1200 Capacitor Replacement Guide
Documentation
[edit | edit source]- Amiga 1200 Schematics: Commodore's main board schematic 364717 for Rev. 1 to 1D, in two scans.
Gallery
[edit | edit source]-
An A1200 main board in the lower case, with a trapdoor card fitted
Related pages
[edit | edit source]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 Amiga 1200—link(accessed 2026-10-01) Launch date and UK price, processor clock, memory, Kickstart versions, the 23 W supply, Escom floppy drives.
- ↑ 2.0 2.1 2.2 2.3 2.4 Commodore, A1200 main board schematic 364717, "A1200 REV 1->1D PCB" (1992), sheet 1, key components table, hosted at Amiga 1200 Schematics.
- ↑ 3.0 3.1 Amiga 500/600/1200 power supply—link(accessed 2026-10-01) A600/A1200 supply 391029-02 and -03: 3.0 A at +5 V, 0.5 A at +12 V, 0.1 A at −12 V, 22.2 W.
- ↑ 4.0 4.1 Commodore A1200—link(accessed 2026-10-01) Revision list and changes; "Battery Backed-Up Clock: No".
- ↑ Amiga A1200 real-time clock module (RTC), June 2017—link(accessed 2026-10-01) The clock is "shown in the schematics as an optional item but was never installed in any of the board revisions to my knowledge".
- ↑ Amiga 1200—link(accessed 2026-10-01)
- ↑ Scuzzblog, December 2023—link(accessed 2026-10-01)
- ↑ Ian Stedman, Amiga power supply guide—link(accessed 2026-10-01)