A2386SX

classic Classic list List threaded Threaded
5 messages Options
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

A2386SX

silverdr-2

I tried to find what are the EPROM chips on that board without destroying their original labels. One is the BIOS, which is probably a '256 EPROM or bigger and the other one I am not even sure if it is an EPROM it's marked with 391171-01. Googling gives me Martin's pages for example

http://mhv.bplaced.net/cbmroms/cbmroms.php

where I can find that it's a 2KiB ROM (?) called 8242/8742

http://mhv.bplaced.net/cbmroms/8242.htm

Interesting capacity for a 40 pin chip... could someone shed some light on what it actually is?

Also I don't seem to be able to locate the schematics for the A2386SX. Do we have any? There seem to be only 2286 on zimmers.

--
SD! - http://e4aws.silverdr.com/


       Message was sent through the cbm-hackers mailing list
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: A2386SX

Konrad B

where I can find that it's a 2KiB ROM (?) called 8242/8742

http://mhv.bplaced.net/cbmroms/8242.htm

Interesting capacity for a 40 pin chip... could someone shed some light on what it actually is?

MCS-48
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: A2386SX

Ethan Dicks
In reply to this post by silverdr-2
On Tue, Jul 18, 2017 at 4:50 PM,  <[hidden email]> wrote:

>
> I tried to find what are the EPROM chips... and the other one I am not even sure if it is an EPROM it's marked with 391171-01. Googling gives me Martin's pages for example
>
> http://mhv.bplaced.net/cbmroms/cbmroms.php
>
> where I can find that it's a 2KiB ROM (?) called 8242/8742
>
> http://mhv.bplaced.net/cbmroms/8242.htm
>
> Interesting capacity for a 40 pin chip... could someone shed some light on what it actually is?

It's a so-called "keyboard BIOS" chip - really a microcontroller to
speak AT-keyboard protocol to a PC-AT|PS/2 keyboard with a parallel
interface for the PC side.  Once standalone, long since folded into PC
motherboard "chipsets", and as Konrad B mentioned it's an MCS/48
family MCU.  An ancestor is the Intel 8048.

https://en.wikipedia.org/wiki/Intel_MCS-48

-ethan

       Message was sent through the cbm-hackers mailing list
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: A2386SX

silverdr-2
In reply to this post by Konrad B

> On 2017-07-18, at 22:59, Konrad B <[hidden email]> wrote:
>
> MCS-48

> On 2017-07-18, at 23:22, Ethan Dicks <[hidden email]> wrote:
>
> It's a so-called "keyboard BIOS" chip - really a microcontroller to
> speak AT-keyboard protocol to a PC-AT|PS/2 keyboard with a parallel
> interface for the PC side.  Once standalone, long since folded into PC
> motherboard "chipsets", and as Konrad B mentioned it's an MCS/48
> family MCU.  An ancestor is the Intel 8048.

Thanks guys. That explains. A uC with EPROM on it makes much more sense

As for the A2386SX schematics - do we have any?

--
SD! - http://e4aws.silverdr.com/


       Message was sent through the cbm-hackers mailing list
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: A2386SX

Gerrit Heitsch
On 07/18/2017 11:29 PM, [hidden email] wrote:

>
>> On 2017-07-18, at 22:59, Konrad B <[hidden email]> wrote:
>>
>> MCS-48
>
>> On 2017-07-18, at 23:22, Ethan Dicks <[hidden email]> wrote:
>>
>> It's a so-called "keyboard BIOS" chip - really a microcontroller to
>> speak AT-keyboard protocol to a PC-AT|PS/2 keyboard with a parallel
>> interface for the PC side.  Once standalone, long since folded into PC
>> motherboard "chipsets", and as Konrad B mentioned it's an MCS/48
>> family MCU.  An ancestor is the Intel 8048.
>
> Thanks guys. That explains. A uC with EPROM on it makes much more sense
>
> As for the A2386SX schematics - do we have any?

Here's a link to check out:

http://www.traumstation.ch/hardware/Commodore/Amiga/A2286-A2386%20Bridgeboard/


  Gerrit


       Message was sent through the cbm-hackers mailing list
Loading...