a500 1.3 and 3.1 KS switch from sordan. Wrong cut pins?

oggie · 31 January 2018, 21:31

I purchased a ks switch from sordan:
https://sordan.ie/product/550/dual-d...600--switcher/

But I think the pins that are cut are on the wrong end of the adapter. If you look at the image of the one I received :

Click image for larger version

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, and compare it to the one on sordan's site here it appears to be different.

I emailed them, but they never replied...

I just need the board, not another KS. Even if I had the PCB design, I could have one built.

Allen1 · 31 January 2018, 22:36

Is the Eprom on your board the same way round as the one in the "big.jpg" ?
If so then it does look like someone chopped of the wrong legs, if that is the case, find someone who can swap the leg/sockets over.

Remove the Kickstart Eprom and desolder the 2 front and 2 back sockets and swap them over

oggie · 31 January 2018, 23:08

Quote:

Originally Posted by Allen1

Is the Eprom on your board the same way round as the one in the "big.jpg" ?
If so then it does look like someone chopped of the wrong legs, if that is the case, find someone who can swap the leg/sockets over.

Remove the Kickstart Eprom and desolder the 2 front and 2 back sockets and swap them over

Yes, the EPROM is the same way on both.

Sent from my Pixel 2 using Tapatalk

kipper2k · 01 February 2018, 00:01

Hi,

Pins 1 and 42 are not used on a dual boot Kickstart. I am assuming it is a 27c800 eprom so toggling the switch sending A18 to ground or 5v will cause the upper or lower 512k portion of the eprom to be in use.

I don't think that board will work with Rev3 or Rev5 Amiga 500 without a modification, there is no mention of it on that site. the only A500 shown is a Rev6a

On that romboard, Vcc and A11 pins have been cut accidentally it appears

oggie · 01 February 2018, 02:09

Quote:

Originally Posted by kipper2k

Hi,

Pins 1 and 42 are not used on a dual boot Kickstart. I am assuming it is a 27c800 eprom so toggling the switch sending A18 to ground or 5v will cause the upper or lower 512k portion of the eprom to be in use.

I don't think that board will work with Rev3 or Rev5 Amiga 500 without a modification, there is no mention of it on that site. the only A500 shown is a Rev6a

On that romboard, Vcc and A11 pins have been cut accidentally it appears

I tried it on a 6a and of course it didn't work. And looking at the board, the switch does short a18 to 5v and they have cut the vcc pin. I guess I'll have to swap the pins then.

oggie · 01 February 2018, 02:40

Quote:

Originally Posted by oggie

I tried it on a 6a and of course it didn't work. And looking at the board, the switch does short a18 to 5v and they have cut the vcc pin. I guess I'll have to swap the pins then.

I looked up the 27c800. A18 is pin 1. But you said pins 1 and 42 are not used.

kipper2k · 01 February 2018, 02:45

Quote:

Originally Posted by oggie

I looked up the 27c800. A18 is pin 1. But you said pins 1 and 42 are not used.

Thats right, as you can see, pin 1 and 42 do not sit in the 40 pin socket, they just overhang...

BUT... Pin 18 is actually used on the Eprom to control the addressing. The Amiga 600 does not need to see A18. The romboard is wired so that the jumper will put the chip in Hi/Lo mode to control which 512k of address is accessed by the Eprom

oggie · 01 February 2018, 02:48

Ok. that makes sense.

I also decided to pop out the ROM and it appears that they put the rom in backwards based on the silkscreen. The round notch is on the opposite end of the ROM. So if I put it in to match the silkscreen, the cut pins would now be pins 1 and 42.

But... this puts the jumper header on the opposite end of the socket, and is completely wrong based on the photos on sordan.ie

And then the jumper header pins are now touching the crystal casing, which I would assume would be grounded.

kipper2k · 01 February 2018, 02:54

Quote:

Originally Posted by oggie

Ok. that makes sense.

I also decided to pop out the ROM and it appears that they put the rom in backwards based on the silkscreen. The round notch is on the opposite end of the ROM. So if I put it in to match the silkscreen, the cut pins would now be pins 1 and 42.

But... this puts the jumper header on the opposite end of the socket, and is completely wrong based on the photos on sordan.ie

And then the jumper header pins are now touching the crystal casing, which I would assume would be grounded.

i will show you the one i make, hang on...

this is similar chip, in TSOP format, you can see that pin 1 and 42 is not needed. This board will work in all versions of Amiga 500s, and using 2 of them side by side will allow them to work in an a1200. I ground off part of the top left corner to allow for another board i was testing

oggie · 01 February 2018, 03:19

ok. so if I put the chip in correctly, pins 1 and 42 are not connected to the socket, and the switch would then either supply GND or VCC to a18 on pin 1. That make sense, right?

But it still doesn't work in my 6a, nor does it fit right since the header pins are hitting the crystal (I put a non-conductive sheet between them), and it doesn't match the diagrams on that site.

Not sure what to do at this point. They won't respond, and I've already spent the money on it. I have a licensed dual ROM ( I assume), and no way to use it.

Sigh.

kipper2k · 01 February 2018, 03:24

Quote:

Originally Posted by oggie

ok. so if I put the chip in correctly, pins 1 and 42 are not connected to the socket, and the switch would then either supply GND or VCC to a18 on pin 1. That make sense, right?

But it still doesn't work in my 6a, nor does it fit right since the header pins are hitting the crystal (I put a non-conductive sheet between them), and it doesn't match the diagrams on that site.

Not sure what to do at this point. They won't respond, and I've already spent the money on it. I have a licensed dual ROM ( I assume), and no way to use it.

Sigh.

K, you need to replace the pins 21 and 22 (on the right edge)

-pins 1 and 42 will not connect to the amiga.
- make sure pins 21 and 22 go into the far right socket holes

also check that pin 1 of the 27c800 is pointing on the left side of amiga. 1 thing to note is some Amigas have 42 pin sockets and 40 pin sockets but regardless, nothing should plug into pin 1 and 42 of the socket if one is installed

oggie · 01 February 2018, 03:31

ok. thanks.

I will do that tomorrow night and report back.

Thanks! That's the last time I buy from them. I'll be getting stuff from you next time.

kipper2k · 01 February 2018, 03:41

Quote:

Originally Posted by oggie

ok. thanks.

I will do that tomorrow night and report back.

Thanks! That's the last time I buy from them. I'll be getting stuff from you next time.

one more thing, putting the eprom in backward or offsetting by one pin is usually fatal for the eprom

oggie · 01 February 2018, 03:45

not what I wanted to hear, but c'est la vie.

oggie · 01 February 2018, 14:06

so I swapped the pins and it didn't make a difference. Still black screen.

I tested it, and it is switching 5v to pin 1 (a18) , so I'm pretty sure the connections are correct. I suspect, like you said, the eeprom is toast. But is it toast permanently? Can I reprogram it?

Will a tl866a reprogram it? Not sure how involved it is to put two KS on it. I read somewhere you also have to do byte swapping?

kipper2k · 01 February 2018, 14:42

Quote:

Originally Posted by oggie

so I swapped the pins and it didn't make a difference. Still black screen.

I tested it, and it is switching 5v to pin 1 (a18) , so I'm pretty sure the connections are correct. I suspect, like you said, the eeprom is toast. But is it toast permanently? Can I reprogram it?

Will a tl866a reprogram it? Not sure how involved it is to put two KS on it. I read somewhere you also have to do byte swapping?

Hi,

here is info on a dual boot KS using 2 different 512K rom images...

http://eab.abime.net/showthread.php?t=46636

once an eprom is fried by misplacement it is normally gone forever. To see if its ok, you will need to remove label and expose to UV light to erase and then you can try to reprogram and verify. This is the reason i switched to the 29F800s as they are electrically erasable and much easier to work with.

oggie · 01 February 2018, 14:45

well, if it is a 27c800, then it's uv erase.. I don't have a uv light.

I suspect it is since I can feel a bump under the cloanto sticker.

kipper2k · 01 February 2018, 14:47

Quote:

Originally Posted by oggie

well, if it is a 27c800, then it's uv erase.. I don't have a uv light.

I suspect it is since I can feel a bump under the cloanto sticker.

.

Yah, it will be UV erasable, without a UV light you are pooped, and of course if you screw up a blank one then you have to use another, not fun.

oggie · 01 February 2018, 14:49

I'm a bit angry at this point. I spent a lot of money for this and it's now useless.

I could put a lot of effort in trying to fix it and still be a waste of time. I've already wasted a lot of time on it.

And they still haven't responded.

kipper2k · 01 February 2018, 14:52

Quote:

Originally Posted by oggie

I'm a bit angry at this point. I spent a lot of money for this and it's now useless.

I could put a lot of effort in trying to fix it and still be a waste of time. I've already wasted a lot of time on it.

And they still haven't responded.

I have some of the 29f800 type, i have been intending on selling them for about 19 euro, (this includes the sticker) people are normally interested in the diagrom/KS3.1 combination

31 January 2018, 21:31	#1
oggie Registered User Join Date: Apr 2017 Location: Quispamsis Posts: 89	a500 1.3 and 3.1 KS switch from sordan. Wrong cut pins? I purchased a ks switch from sordan: https://sordan.ie/product/550/dual-d...600--switcher/ But I think the pins that are cut are on the wrong end of the adapter. If you look at the image of the one I received : , and compare it to the one on sordan's site here it appears to be different. I emailed them, but they never replied... I just need the board, not another KS. Even if I had the PCB design, I could have one built.

01 February 2018, 00:01	#4
kipper2k Registered User Join Date: Sep 2006 Location: Thunder Bay, Canada Posts: 4,323	Hi, Pins 1 and 42 are not used on a dual boot Kickstart. I am assuming it is a 27c800 eprom so toggling the switch sending A18 to ground or 5v will cause the upper or lower 512k portion of the eprom to be in use. I don't think that board will work with Rev3 or Rev5 Amiga 500 without a modification, there is no mention of it on that site. the only A500 shown is a Rev6a On that romboard, Vcc and A11 pins have been cut accidentally it appears Last edited by kipper2k; 01 February 2018 at 00:08.

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31 January 2018, 22:36	#2
Allen1 Registered User Join Date: Nov 2009 Location: Blyth England Age: 68 Posts: 786	Is the Eprom on your board the same way round as the one in the "big.jpg" ? If so then it does look like someone chopped of the wrong legs, if that is the case, find someone who can swap the leg/sockets over. Remove the Kickstart Eprom and desolder the 2 front and 2 back sockets and swap them over

01 February 2018, 02:48	#8
oggie Registered User Join Date: Apr 2017 Location: Quispamsis Posts: 89	Ok. that makes sense. I also decided to pop out the ROM and it appears that they put the rom in backwards based on the silkscreen. The round notch is on the opposite end of the ROM. So if I put it in to match the silkscreen, the cut pins would now be pins 1 and 42. But... this puts the jumper header on the opposite end of the socket, and is completely wrong based on the photos on sordan.ie And then the jumper header pins are now touching the crystal casing, which I would assume would be grounded.

01 February 2018, 03:19	#10
oggie Registered User Join Date: Apr 2017 Location: Quispamsis Posts: 89	ok. so if I put the chip in correctly, pins 1 and 42 are not connected to the socket, and the switch would then either supply GND or VCC to a18 on pin 1. That make sense, right? But it still doesn't work in my 6a, nor does it fit right since the header pins are hitting the crystal (I put a non-conductive sheet between them), and it doesn't match the diagrams on that site. Not sure what to do at this point. They won't respond, and I've already spent the money on it. I have a licensed dual ROM ( I assume), and no way to use it. Sigh.

01 February 2018, 03:31	#12
oggie Registered User Join Date: Apr 2017 Location: Quispamsis Posts: 89	ok. thanks. I will do that tomorrow night and report back. Thanks! That's the last time I buy from them. I'll be getting stuff from you next time.

01 February 2018, 03:45	#14
oggie Registered User Join Date: Apr 2017 Location: Quispamsis Posts: 89	not what I wanted to hear, but c'est la vie.

01 February 2018, 14:06	#15
oggie Registered User Join Date: Apr 2017 Location: Quispamsis Posts: 89	so I swapped the pins and it didn't make a difference. Still black screen. I tested it, and it is switching 5v to pin 1 (a18) , so I'm pretty sure the connections are correct. I suspect, like you said, the eeprom is toast. But is it toast permanently? Can I reprogram it? Will a tl866a reprogram it? Not sure how involved it is to put two KS on it. I read somewhere you also have to do byte swapping?

01 February 2018, 14:45	#17
oggie Registered User Join Date: Apr 2017 Location: Quispamsis Posts: 89	well, if it is a 27c800, then it's uv erase.. I don't have a uv light. I suspect it is since I can feel a bump under the cloanto sticker.

01 February 2018, 14:49	#19
oggie Registered User Join Date: Apr 2017 Location: Quispamsis Posts: 89	I'm a bit angry at this point. I spent a lot of money for this and it's now useless. I could put a lot of effort in trying to fix it and still be a waste of time. I've already wasted a lot of time on it. And they still haven't responded.

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