A1000 Kickstart ROM hack
 

DISCLAIMER: The following information is presented on an "as is" basis.
Whilst every effort was made to ensure accuracy, responsibility for your
equipment and potential damage to it, as well as any potential personal
injury is entirely your own.

.
This project has been succesfully carried out on two A1000's that I own, both of which are older
models with a daughterboard. I can't guarantee that this modification will work for the newer,
daughterboard-less A1000's, although I can't see any reason why it shouldn't.
 
Special thanks go to Chris Ralph who may have come up with this hack and Ross Vumbaca
for mailing (the old fashioned way ;-) this information out to me.
 
The procedure:
(not for the faint hearted)
 
Firstly, you need to solder wires from the 68000 CPU to the Kickstart ROM. The way I did it was to use a 68000 socket with extra long legs through some veroboard and then wired the 68000 CPU socket to the ROM socket. The extra length of the CPU socket legs meant I could push them straight into the motherboard CPU socket and still have enough clearance.You can solder directly to the CPU and ROM, but that makes it hard to change the ROM and doesn't look very neat.
 
Refer to this page for some pictures that show how I did it.
 
The connections between the CPU and Kickstart ROM's are as follows:
 
CPU  
PIN #
ROM
PIN#
CPU 
PIN #
ROM 
PIN #
1
22
40
37
2
19
41
36
3
17
42
35
4
15
43
34
5
13
44
33
14
21and31
45
32
16
30
46
1
29
9
54
29
30
8
55
27
31
7
56
25
32
6
57
23
33
5
58
20
34
4
59
18
35
3
60
16
36
2
61
14
37
40
62
28
38
39
63
26
39
38
64
24
 
Pin 13 of the ROM goes to DAUGEN (U6L), see below...
 

1. Disable WOM by cutting track from pin 17 on DAUGCAS (U6J) - this goes to both 74LS373 buffers (U4H and U4K) You need to lift and invert the daughterboard from the main board to do this.

2. Pull up both 74LS373 buffers by connecting a 4.7Kohm resistor between pins 1 and 20 on U4K. Pin 1 on both buffers should already be connected by a motherboard trace, but if they are not you will need to use a second 4.7Kohm resistor to pull up buffer U4H pins 1 and 20.

3. Remove the KickROM's. These are located just left of the 68000 CPU and below the 8520's. (U5N even and U5P odd)

4. Plug in the 68000 CPU with your ROM connected and solder the wire from pin 12 on the Kickstart ROM to pin 13 of DAUGEN (U6L) on the daughterboard. Use a reasonable length of wire so you have enough slack to remove the daughterboard.

5. Carry out the PAL grounding hack if your machine hasn't already had it performed. This hack helps reduce bus noise which the older A1000models are prone to. Simply solder a reasonable heavy wire from pin 10 (Ground) on the 4 PAL's (U6J, U6K, U6L, U6N) to a good ground on the mainboard.

That is it, reassemble and power up... and with some measure of luck you can throw that Kickstart disk in the bin. I have tried a 2.05 ROM in place of the 1.3 ROM and that also worked just fine. I have no doubt that a 3.1 ROM should work also.
 
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