PDA

View Full Version : Closed KS ROM autoswitch for A500 A2000 NOS



tbtorro
8th August 2011, 21:30
Please see the old thread here: http://www.amibay.com/showthread.php?t=18271

tbtorro
11th August 2011, 23:43
Price drop.

tokyoracer
12th August 2011, 12:52
I know the original thread is elsewhere but I received mine ok, thanks. :)

davideo
12th August 2011, 12:58
I know the original thread is elsewhere but I received mine ok, thanks. :)

It's here http://www.amibay.com/showthread.php?t=18271

Dave G :cool:

tbtorro
13th August 2011, 00:34
I know the original thread is elsewhere but I received mine ok, thanks. :)
Feedback returned.

Draxx
14th August 2011, 15:03
Do these work in A600 also?

tbtorro
14th August 2011, 16:18
Do these work in A600 also?


@dwayneh
Yes but you will have to cut the clip-on plugs off and e.g. solder the wires directly on the equivalent pins of the matching A600 chips (more than likely the two CIAs).
Or maybe you could determine the kind of logical condition the device expects on the two wires in order to switch KS and provide your own circuitry to emulate it.

Yes if you have serious DIY skills and proper tools.

BLTCON0
14th August 2011, 17:01
@Draxx
Apparently these are the Alfa Data ROM switchers. The black wireclip goes to Gary and the red wireclip goes to ODD_CIA. According to the function logic, the black one should go to the RESET pin of Gary (pin 41) and the red one to the FIRE_0 pin of ODD_CIA (pin #8), on the A500. This visually matches the instruction sheet as seen on tbtorro's photos. The equivalent on an A600 would be pin 40 of Gayle and pin 10 of U7 (ODD_CIA).
Naturally, pin 11 of U7 (fire button on the second port) could also be used if a joystick is connected there.
Gayle is 84 pin sq. PLLC and CIAs are 44 pin sq. PLLC, maybe through-hole PLLC sockets could be clipped-on for easier connection.

@tbtorro
Can you post a higher resolution photo of the instructions sheet to verify the GARY/CIA pin assumptions?

tbtorro
14th August 2011, 17:17
As you wish. C8<


@Draxx
Apparently these are the Alfa Data ROM switchers. The black wireclip goes to Gary and the red wireclip goes to ODD_CIA. According to the function logic, the black one should go to the RESET pin of Gary (pin 41) and the red one to the FIRE_0 pin of ODD_CIA (pin 8), on the A500. This visually matches the instruction sheet as seen on tbtorro's photos. The equivalent on an A600 would be pin 40 of Gayle and pin 10 of U7 (ODD_CIA).
Naturally, pin 11 of U7 (fire button on the second port) could also be used if a joystick is connected there.
Gayle is 84 pin sq. PLLC and CIAs are 44 pin sq. PLLC, maybe through-hole PLLC sockets could be clipped-on for easier connection.

@tbtorro
Can you post a higher resolution photo of the instructions sheet to verify the GARY/CIA pin assumptions?

BLTCON0
14th August 2011, 17:30
Excellent! :thumbsup:
So it doesn't use pin 41 but pin 5 (the reset signal from the keyboard MPU). The equivalent on Gayle on the A600 is pin 63.

VidChick
15th August 2011, 09:17
Hi.. so does this mean it WILL work on A600? (I have 2 coming in yay ) :roll:

tbtorro
15th August 2011, 11:14
Hi.. so does this mean it WILL work on A600? (I have 2 coming in yay ) :roll:

If I deduce BLTCON's findings correctly it will, however most of the A600's chips are non-socketed and has a higher component density than the A500 so soldering will be unavoidable. But someone please correct me if I'm wrong. C8<

jope
15th August 2011, 13:38
If I deduce BLTCON's findings correctly it will, however most of the A600's chips are non-socketed and has a higher component density than the A500 so soldering will be unavoidable. But someone please correct me if I'm wrong. C8<

The kickstart ROM is socketed in most A600s. I've heard of some that had it soldered in, but I've never seen an A600 like that myself.