Gayle in A500+

[bebek]

Hi,
Hope everyone had good Christmas time. I gave up with Apollo 060 and think about HDD in my A500+. So, I am thinking about fitting Gayle into A500+. I have got a spare A600 I can use Gayle from (and whatever more is needed).It is going to be a big spider .
Two choices:

1. only for HDD interfacing,
2. complete replacement of Gary

I am not interested with PCMCIA card so I will leave this part of Gayle unused. I have done some research on pins and signals and looks like Gayle covers most of Gary's signals. My plan is to replace U10...U13 with two 74LS245 (like in A600). The clock is 14MHz for Gayle instead 7MHz of Gary - should not be a problem if I will follow A600 schematics. I do not know where from take EXRAM signal. I would like to keep bottom memory expansion working. Can somebody tell what signals of Gayle are needed to run hard drive only? Do you think it will work? Any help will be appreciated.

[rkauer]

http://www.students.tut.fi/~leinone3/ide/ide68k.html

[bebek]

Originally Posted by rkauer

http://www.students.tut.fi/~leinone3/ide/ide68k.html

I know that but I have got Gayle and it would be nice if I can implement it to A500 and see it working . It does not look like rocket science.

[alexh]

There are A500 accelerators which plug into nothing more than the 68000 socket which include Gayle chips for just IDE. The Gary chip remains in use.

http://amiga.resource.cx/exp/ematrix530

But making your own board is false economy. You'll never make one for under the cost of a CFIDE68k

[bebek]

It will not cost anything, only time. I have all parts I need, no pcb - only spider of cables. I want to do it only for fun, to see if it can be done.

[alexh]

Originally Posted by bebek

no pcb - only spider of cables

I wish you luck but I also bet money it never works. I do not believe that something like this is simply a wiring exercise. I used to design my first PCB's as simple wiring looms. All but the simplest never ever worked.

Remember you'll need lots of discretes (resistors & capacitors) wiring data signals not only to their destination but to power and ground for termination and pull up. Especially if it is to be connected to a hard drive.

Do not consider replacing the Gary (I mean what is the point?). Just work on adding it as the IDE controller.

The schematics and CPLD code for the IDE68k should give you an insight into what is required in terms of connections to Gayle, just for IDE. See rkauer's link above.

[bebek]

That is ok, many things I started did not work (like Apollo 060 for example and first marriage ) but I keep trying .I have to break my holiday and go to work for a while to take Gayle off A600 and then will try to make Amiga see it.

[Shadowfire]

It will never work with wires. I'm in agreement with alexh on this one. You are much better off going with a tested project like the CFIDE68K.

[Zetr0]

@bebek

I believe that you could possibly get away with a lot if you make your own PCB

Copper boards £4.44 for 5 plates (inc postage)

Press and peel £3.50 (inc postage)

You will also need some software
Eagle CAD - Windows or Eagle CAD - Linux

for interfacing the Gayle chip it would be best to source your needs from the CPU socket, perhaps even design a board that plugs into it, like the 68KIDE.

However if you are going this far it would be better just to revise your design to take a CPLD I think a 72 macro cell should do the trick (i will have to check)

Bottom line-

You can probably interface a Gayle IC into an A500+, however theres no way it will work on just a wire loom, and thats even before you look at signal degredation, power disspation, IC Latching and a whole lot more too boot -

You will need to make a PCB with both descrete and glue-logic to make it happen.

It would be cool, and worth of much hardware pr0n indeed! =D

[bebek]

Originally Posted by Zetr0

@bebek

I believe that you could possibly get away with a lot if you make your own PCB

Copper boards £4.44 for 5 plates (inc postage)

Press and peel £3.50 (inc postage)

You will also need some software
Eagle CAD - Windows or Eagle CAD - Linux

for interfacing the Gayle chip it would be best to source your needs from the CPU socket, perhaps even design a board that plugs into it, like the 68KIDE.

However if you are going this far it would be better just to revise your design to take a CPLD I think a 72 macro cell should do the trick (i will have to check)

Bottom line-

You can probably interface a Gayle IC into an A500+, however theres no way it will work on just a wire loom, and thats even before you look at signal degredation, power disspation, IC Latching and a whole lot more too boot -

You will need to make a PCB with both descrete and glue-logic to make it happen.

It would be cool, and worth of much hardware pr0n indeed! =D

Thanks for advice, I did not know about this method of pcb making. Last time I was making my own pcb was 15 years ago with oil marker - was not pretty. I am using Protel99SE - I hope it will be enough. I will read about this method and if the spider works I will make pcb . I know it is a big IF. Scared Gayle is already on bench, waiting ... .

[bebek]

Is there any software that shows that Gayle is installed, without hard drive connected ?

[Zetr0]

@bebek

I am not sure but sys info might be able to help.

[bebek]

Originally Posted by Zetr0

@bebek

I am not sure but sys info might be able to help.

It shows Gary's version ... but Gary will be there too , unless it will run scsi.device only if Gayle is found .

[bebek]

Small update, first attempt - I can not see run scsi.device in sysinfo so it is fail but I do not give up yet. Amiga boots, touched k_reset on gayle and it resets so something is alive . Next step is pull-up resistors on all unused inputs. It will take some time.

[chue]

The link in post #2 in this thread is dead. Here's a link to a copy at archive.org:

https://web.archive.org/web/20150720...de/ide68k.html