Strange box

From: Joe <rigdonj_at_intellistar.net>
Date: Thu May 25 22:50:37 2000

At 11:41 PM 5/25/00 +0100, Tony wrote:
>> I think Tony is right about it beins some kind of buffer box. I wish it
>> was some kind of small computer! There are a couple more where I found this
>
>Well, technically, it is a computer (it's got a microprocessor in it),
>but it may well not be user-programmable :-(.

   Ok OK.
>
>> one. I opened it this morning and it has has a 8085AH CPU in it along with
>> a 8212 IC (8 bit latch) and two 8156 ICs (8 x 256 bit SRAM with timer and
>> I/O ports) in it along with a lot of SSI TTL chips. All the ICs seem to be
>
>Two things which you don't mention...
>
>Firstly, any kind of ROM/EPROM.

 Yes.

There must be something for it to execute
>on power-on. Is there an EPROM in there? If there is, and you can make a
>dump of it, then it's worth running strings(1) (a unix program that finds
>text strings in a binary file) (or a similar program under another OS).
>Sometimes you'll find what's clearly a list of commands or something in
>the EPROM.

   I've thoguht of that. I'll do it if I get the time. One of the list
members thinks he may have a manual for it. I'll see what he finds first.
>
>Secondly, you don't mention any kind of disk controller chip. From which
>I conclude it doesn't use one. This almost certainly means that the
>format is non-standard, and probably something that no other machine
>could read or write. It might be hard-sectored (look at the original
>disk).

No, the disk is sided sided, double density and soft sectored. There's no
disk controller IC in it.

It might read/write a track at a time. It might even put
>_asynchronous_ data (from some kind of UART) onto the disk -- I've seen
>that done once or twice!

   How can you check for that? Other than monitoring with a scope while
it's in operation. Is there any way to check the disk and tell?

    
    Joe
>
>-tony
>
>
Received on Thu May 25 2000 - 22:50:37 BST

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