A1200

Variants

A1200 by Commodore
A1200 by Amiga Technologies

In 1992 December Commodore released the A1200, its most popular Amiga model, based on the AGA chip set. From 1994 April to 1995 May no Amigas were produced when the new owner, Escom, created a division called Amiga Technologies and restarted the production of the A1200 and A4000T.

Processor

68020 @ 14-28 MHz
68030 @ 25-50 MHz
68040 @ 25-40 MHz
68060 @ 50-75 MHz
PowerPC 603e @ 160-240 MHz

All A1200s have a 68EC020 @ 14.28 MHz soldered to their motherboard. Upgrading the processor requires the use of a processor card which can be installed into the trapdoor slot.
A 68881 or 68882 floating point unit can be installed on the motherboard, but no socket is provided.

Memory

2 MB Chip RAM
up to 256 MB Fast RAM on processor cards
up to 4 MB Fast RAM on PCMCIA cards

The A1200 has 2 MB 70 ns Chip RAM soldered to its motherboard which could not be expanded further.
Although the A1200 is an entirely 32 bit machine, the 68EC020 processor has only 24 bit address space (16 MB) besides its 32 bit data path. This allows 8 MB for Fast RAM expansion which can be added either via a PCMCIA card or via the trapdoor expansion slot. Further expansion of the Fast RAM requires the use of a processor card.

Custom chips

Alice - AGA display controller
Lisa - AGA display encoder
Paula - audio and I/O controller
Gayle - system address decoder and IDE controller
Budgie

Supported screen modes
PAL
NTSC
Euro36
A2024
320×256 - 1280×512
320×200 - 1280×400
320×200 - 1280×400
1024×1024
50 Hz, 15.60 kHz
60 Hz, 15.72 kHz
73 Hz, 15.76 kHz
15 Hz, 15.72 kHz
DblPAL
DblNTSC
Multiscan
Euro72
Super72
320×512 - 640×1024
320×400 - 640×800
640×480 - 640×960
640×400 - 640×800
400×300 - 800×600
50 Hz, 29.45 kHz
59 Hz, 29.20 kHz
60 Hz, 31.44 kHz
70 Hz, 31.43 kHz
72 Hz, 24.62 kHz
Supported palettes
256 from 16 million, 262144 (HAM8)

A1200s manufactured by Commodore shipped with Kickstart 3.0 ROM which can be replaced with a 3.1 one. All the Escom ones have Kickstart 3.1.

Expansion slots

1× processor card slot
1× PCMCIA slot
1× "clock" port

The 150 pin trapdoor expansion slot is designed for processor cards, memory expansions and DMA SCSI controllers.
The 68 pin PCMCIA slot accepts industry standard peripherals if the suitable driver software is present.
The 22 pin clock header was intended to be used for a battery backed up clock and an 1 MB Chip RAM expansion for the never released 1 MB A1200s. Nowadays there exist several expansions like sound cards or I/O controllers.

The A1200 has a vast array of upgrade options, including processor cards, SCSI controllers and many other types of expansion.

Interfaces

1× serial DB25 male, RS232
1× parallel DB25 female, Centronics
1× video DB23 male, analog RGB
1× composite video, RCA jack
1× RF modulated video, RCA jack
2× mouse/game DB9 male
2× stereo audio RCA jack
1× external floppy DB23 female
1× internal floppy 34 pin header
1× internal AT IDE 44 pin header

The built in IDE controller supports two IDE devices connected simultaneously, although there is only one internal drive bay for a 2.5" hard disk drive. Unlike the A4000 the A1200 has a non-buffered IDE port. Only mode PIO 0 is supported.
The floppy drive controller supports up to four devices - one attached to the internal floppy header and three connected to the external floppy port. Both double and high density disk drives are supported. A 880 kB double density floppy disk drive is built into the A1200's compact case.

Motherboard revisions

revision 1A
uses 256k×16 chips for Chip RAM
Budgie rev 0
two full length clock port headers, intended for Chip RAM expansion / flash ROM daughterboard
the mouse port is part of the motherboard
revision 1B
one full length clock port header
revision 1D (Photo)
one half length clock port header
the mouse port is connected with a ribbon cable to the motherboard
revision 2B (Photo)
uses 512k×8 chips for Chip RAM
Budgie rev A
the mouse port is on a separate panel
the +12V is missing from the RGB port - genlocks work only with external power supplies