Macintosh Computers: ROM Version Numbers

To find the ROM revision of a computer not listed in this article, use one of the following two described methods.

Apple System Profiler is the easiest. Launch the program and under the System Profile tab, look in the Production information section for the ROM revision.

Alternatively, you can use the Programmer's Interrupt Switch to determine the ROM version number of your Macintosh Computer.

1. Press the programmer's interrupt switch, or use the keyboard equivalent.

2. Type: DM 2AE

3. Press return.

• This displays the ROMbase global which is located at memory address $0002AE. The ROMbase global is the number located in offset 0 and 2. For example, a Quadra 660AV displays: 4080 0000 XXXX XXXX XXXX XXXX XXXX XXXX

4. Type the ROMbase global. EXAMPLE: DM 40800000. The result is 5BF1 0FD1 0000 002A 077D XXXX XXXX XXXX

5. The machine type and ROM version are at offset 8 or 077D in this case which is from a 660av Macintosh Computer. You could also add the 8 bytes to the memory address and have done DM 40800008 and the first two bytes would be the type and ID.

Macintosh ROM Version Table

System	Machine Type	ROM version
Macintosh 128K	0
Macintosh 512K	0
Macintosh 512Ke	0	75
Macintosh Plus	0	75
Macintosh SE	2	76
Macintosh SE/30	1	78
Macintosh Classic	2	76
Macintosh Classic II	6	7C
Macintosh Color Classic	6	7C
.
Macintosh LC	6	7C
Macintosh LC II	6	7C
Macintosh LC III	6	7C
Macintosh LC 520	6	7C
Macintosh LC 550	6	7C
Macintosh LC 575	6	7C
Macintosh LC 475	6	7C
Macintosh LC 580	6	7C
Macintosh LC 630	6	7C
Macintosh TV	6	7C
.
Performa 200	6	7C
Performa 400, 405, 410, 430	6	7C
Performa 460, 466, 467	6	7C
Performa 475, 476	6	7C
Performa 550, 560	6	7C
Performa 575, 578, 580	6	7C
Performa 600, 600CD	6	7C
Performa 630, 631, 635, 636, 637, 638	6	7C
Performa 5200, 5215	7	7D
Performa 5260, 5300, 5320	7	7D
Performa 6110,6112,6115,6116,6117,6118	7	7D
Performa 6200,6205,6214,6216,6218,6220	7	7D
Performa 6230, 6290, 6300, 6310, 6320	7	7D
Performa 6360	7	7D
Performa 6400	7	7D
.
Macintosh II	1	78
Macintosh IIx	1	78
Macintosh IIcx	1	78
Macintosh IIci	6	7C
Macintosh IIsi	6	7C
Macintosh IIfx	6	7C
.
Macintosh Centris 610	6	7C
Macintosh Centris 650	6	7C
Macintosh Centris 660AV	7	7D
.
Macintosh Quadra 605	6	7C
Macintosh Quadra 610	6	7C
Macintosh Quadra 630	6	7C
Macintosh Quadra 650	6	7C
Macintosh Quadra 660AV	7	7D
Macintosh Quadra 700	6	7C
Macintosh Quadra 800	6	7C
Macintosh Quadra 840AV	7	7D
Macintosh Quadra 900	6	7C
Macintosh Quadra 950	6	7C
.
Macintosh Portable	3	78
PowerBook 100	3	7A
PowerBook 140	6	7C
PowerBook 145	6	7C
PowerBook 145B	6	7C
PowerBook 150	6	7C
PowerBook 160	6	7C
PowerBook 165	6	7C
PowerBook 165c	6	7C
PowerBook 170	6	7C
PowerBook 180	6	7C
PowerBook 180c	6	7C
PowerBook 190	7	7D
PowerBook Duo 210	6	7C
PowerBook Duo 230	6	7C
PowerBook Duo 250	6	7C
PowerBook Duo 270c	6	7C
PowerBook Duo 280	6	7C
PowerBook Duo 280c	6	7C
PowerBook Duo 2300	7	7D
PowerBook 520	6	7C
PowerBook 520c	6	7C
PowerBook 540	6	7C
PowerBook 540c	6	7C
PowerBook 5300	7	7D
.
Power Macintosh 4400/200	7	7D
Power Macintosh 5200/75 LC	7	7D
Power Macintosh 5300/100 LC	7	7D
Power Macintosh 5260/100	7	7D
Power Macintosh 5400/120	7	7D
Power Macintosh 5500/225	7	7D
Power Macintosh 6100 Series	7	7D
Power Macintosh 6500/225 & 6500/250	7	7D
Power Macintosh 7100 Series	7	7D
Power Macintosh 7200 Series	7	7D
Power Macintosh 7300 Series	7	7D
Power Macintosh 7500 Series	7	7D
Power Macintosh 7600 Series	7	7D
Power Macintosh 8100 Series	7	7D
Power Macintosh 8500 Series	7	7D
Power Macintosh 8600 Series	7	7D
Power Macintosh 9500 Series	7	7D
Power Macintosh 9600 Series	7	7D

Notes:

1. The ROM version does not necessarily reflect slight differences in ROM sets. For example, the Macintosh IIfx ROMs are slightly different from the Macintosh IIci ROMs, even though the ROM version number is the same.

2. With the Centris 660AV and Quadra 840AV, a new 2 MB ROM was introduced.