[vcf-midatlantic] Working Tandy 1000 or 2000

Jonathan Gevaryahu jgevaryahu at gmail.com
Fri Aug 31 00:20:25 EDT 2018 

U41 must be 01.03.00, then. (does the Tandy 1000SX display that during 
boot?)
Can you snap a pic of the ROM chip? I need to document the exact label 
on it.

On 8/30/2018 8:18 PM, Kelly Leavitt wrote:
>
> Found a 1000TX in the dungeon. Have to get it out.
>
>
> Took a picture of U41 in my SX, which I believe is the the ROM. It is 
> Tandy part number 8079015. Makers mark is a capital (and serrifed) GI. 
> That does not agree with any ICs on the parts list.
>
>
> Hope this helps.
>
>
> My guess is the Tech Ref is based on 01.01.00. The later version of 
> BIOS has a different internal part number.
>
>
> Kelly
>
>
>
> ------------------------------------------------------------------------
> *From:* Jonathan Gevaryahu <jgevaryahu at gmail.com>
> *Sent:* Thursday, August 30, 2018 3:52 PM
> *To:* Kelly Leavitt; Dean Notarnicola; vcf-midatlantic
> *Subject:* Re: [vcf-midatlantic] Working Tandy 1000 or 2000
> Interestingly, so far the tech manual has been correct about the sound 
> chips.
> The tech manual for the SX however claimed that it uses the "8040328" 
> BIOS, which is version 01.01.00
> but it uses a bios which is 01.02.00, with an unknown number? Maybe 
> some SX machines shipped with the 8040328 and some with whatever the 
> tandy part number is for the later bios?
> Can you snap a pic of the bios chip in your SX?
>
>
> On 8/30/2018 3:20 PM, Kelly Leavitt wrote:
>>
>> OK, I'll see if I have the TX. Based on the (known unreliable) 
>> technical reference manual, the 1000TX uses the NCR 8496.
>>
>>
>>
>> ------------------------------------------------------------------------
>> *From:* Jonathan Gevaryahu <jgevaryahu at gmail.com> 
>> <mailto:jgevaryahu at gmail.com>
>> *Sent:* Thursday, August 30, 2018 2:21 PM
>> *To:* Kelly Leavitt; Dean Notarnicola; vcf-midatlantic
>> *Subject:* Re: [vcf-midatlantic] Working Tandy 1000 or 2000
>> The 1000TX I've heard (but am not sure) uses an NCR8496, but again, 
>> just a rumor.
>>
>> On 8/30/2018 10:23 AM, Kelly Leavitt wrote:
>>>
>>> Just confirmed, my 1000SX has the SN76496 TI chip. I'll have to look 
>>> at the others in this family.
>>>
>>>
>>>
>>> ------------------------------------------------------------------------
>>> *From:* Dean Notarnicola <dnotarnicola at gmail.com> 
>>> <mailto:dnotarnicola at gmail.com>
>>> *Sent:* Wednesday, August 29, 2018 11:48 PM
>>> *To:* vcf-midatlantic
>>> *Cc:* Jonathan Gevaryahu; Kelly Leavitt
>>> *Subject:* Re: [vcf-midatlantic] Working Tandy 1000 or 2000
>>> I just picked up an SX. I'll check it in the morning
>>>
>>> On Wed, Aug 29, 2018 at 11:13 PM Jonathan Gevaryahu via 
>>> vcf-midatlantic <vcf-midatlantic at lists.vcfed.org 
>>> <mailto:vcf-midatlantic at lists.vcfed.org>> wrote:
>>>
>>>     The problem is I've found that the parts lists in some of the Tandy
>>>     manuals is incorrect.
>>>
>>>     On 8/29/2018 10:11 PM, Kelly Leavitt wrote:
>>>     >
>>>     > OK, sorry I got that backward. I have an SX apart on the bench
>>>     for
>>>     > some testing. I cannot find any chip with either part number.
>>>     It is
>>>     > either hiding under a Tandy house number or part of the 2 big
>>>     (for the
>>>     > time) ASICs. I'm pulling up the technical reference manual now.
>>>     >
>>>     >
>>>     > OK, according to the parts list on P51, U37A is an SN76496 Tone
>>>     > Generator. That agrees with page 7 of the schematic.
>>>     >
>>>     >
>>>     > I've attached screen grabs of these if they don't get stripped.
>>>     >
>>>     >
>>>     > You can find the tech ref for the 1000sx at
>>>     >
>>>     ftp://ftp.mindcandydvd.com/pub/drivers/Tandy/Tandy_1000SX_Technical_Reference_Manual.pdf
>>>     >
>>>     >
>>>     > I'll verify the part number of IC U37A tomorrow.
>>>     >
>>>     >
>>>     >
>>>     >
>>>     ------------------------------------------------------------------------
>>>     > *From:* Jonathan Gevaryahu <jgevaryahu at gmail.com
>>>     <mailto:jgevaryahu at gmail.com>>
>>>     > *Sent:* Wednesday, August 29, 2018 9:18 PM
>>>     > *To:* Kelly Leavitt; vcf-midatlantic
>>>     > *Subject:* Re: [vcf-midatlantic] Working Tandy 1000 or 2000
>>>     > The TI chip is fairly well understood; the original Tandy
>>>     1000/1000HD,
>>>     > and the slightly enhanced 1000A used the 'real' TI chip,
>>>     SN76496, for
>>>     > certain.
>>>     > Its possible that the EX (and maybe HX?) also used it, but
>>>     unclear.
>>>     >
>>>     > The SX and TX (and maybe the HX?) SUPPOSEDLY used the weird
>>>     NCR8496
>>>     > chip, which is what I need tested. (assuming wikipedia is
>>>     correct,
>>>     > which it actually isn't regarding the SN76496 on the Tandy
>>>     1000/1000A...)
>>>     > The SL2, TL2, RLX, RSX use the PSSJ-3 ASIC, which would also
>>>     be ok for
>>>     > testing, but ideally I'd like to run these tests on both the
>>>     NCR8496
>>>     > and the PSSJ-3.
>>>     >
>>>     >
>>>     > On 8/29/2018 8:36 AM, Kelly Leavitt wrote:
>>>     >>
>>>     >> I have manyof the 1000 series computers (hx, ex, sx, sl, sl2,
>>>     tl,
>>>     >> etc). Do you know which used the wonky TI chip? I can always
>>>     start
>>>     >> opening them up.
>>>     >>
>>>     >>
>>>     >>
>>>     >>
>>>     ------------------------------------------------------------------------
>>>     >> *From:* Jonathan Gevaryahu <jgevaryahu at gmail.com
>>>     <mailto:jgevaryahu at gmail.com>>
>>>     >> <mailto:jgevaryahu at gmail.com <mailto:jgevaryahu at gmail.com>>
>>>     >> *Sent:* Wednesday, August 29, 2018 12:55 AM
>>>     >> *To:* Kelly Leavitt; vcf-midatlantic
>>>     >> *Subject:* Re: [vcf-midatlantic] Working Tandy 1000 or 2000
>>>     >> Another thing: I need to test against a tandy 1000-series
>>>     with an
>>>     >> NCR8496 or PSSJ-1 asic in it, i.e. not the original tandy
>>>     >> 1000/1000a/1000hd, since they actually use a real TI SN76496 PSG
>>>     >> which actually behaves differently! (that's the whole reason
>>>     I need
>>>     >> to do these tests, the behavior isn't consistent!)
>>>     >>
>>>     >>
>>>     >> On 8/29/2018 12:53 AM, Jonathan Gevaryahu wrote:
>>>     >>> Indeed, I was thinking of the 1000 series, not the 2000.
>>>     >>> I'm trying to figure the best way to run the tests from
>>>     basic, i
>>>     >>> might need to mess around with dosbox to get the program
>>>     written,
>>>     >>> since MAME has keyboard issues with the tandy machines
>>>     (which I'd
>>>     >>> also love to fix...)
>>>     >>>
>>>     >>>
>>>     >>>
>>>     >>> On 8/28/2018 8:45 PM, Kelly Leavitt wrote:
>>>     >>>>
>>>     >>>> The 2000 and the 1000 were remarkably different beasts. The
>>>     2000
>>>     >>>> had a basic speaker that did beeps. There was a rumored TV
>>>     board
>>>     >>>> but I have never seen one in the wild. Fun tidbit, the 2000
>>>     loaded
>>>     >>>> BIOS from floppy (a 720k 5.25 inch floppy). The built in
>>>     ROM was a
>>>     >>>> simple boot loader.
>>>     >>>>
>>>     >>>>
>>>     >>>> The 1000 was mostly compatible with the XT/jr with some
>>>     added sound
>>>     >>>> and graphics capabilities.
>>>     >>>>
>>>     >>>>
>>>     >>>> I have working models of the 1000 hear that I cant test with
>>>     >>>> Tandy's Basica if you'd like. My 2000's are iffy so I can't
>>>     make
>>>     >>>> any promises. Send me the pokes you'd like to try.
>>>     >>>>
>>>     >>>>
>>>     >>>> Kelly
>>>     >>>>
>>>     >>>> kelly at catcorner.org <mailto:kelly at catcorner.org>
>>>     <mailto:kelly at catcorner.org <mailto:kelly at catcorner.org>>
>>>     >>>>
>>>     >>>>
>>>     >>>>
>>>     >>>>
>>>     ------------------------------------------------------------------------
>>>     >>>> *From:* vcf-midatlantic
>>>     <vcf-midatlantic-bounces at lists.vcfed.org
>>>     <mailto:vcf-midatlantic-bounces at lists.vcfed.org>>
>>>     >>>> <mailto:vcf-midatlantic-bounces at lists.vcfed.org
>>>     <mailto:vcf-midatlantic-bounces at lists.vcfed.org>> on behalf of
>>>     >>>> Jonathan Gevaryahu via vcf-midatlantic
>>>     >>>> <vcf-midatlantic at lists.vcfed.org
>>>     <mailto:vcf-midatlantic at lists.vcfed.org>>
>>>     >>>> <mailto:vcf-midatlantic at lists.vcfed.org
>>>     <mailto:vcf-midatlantic at lists.vcfed.org>>
>>>     >>>> *Sent:* Sunday, August 26, 2018 5:16 AM
>>>     >>>> *To:* vcf-midatlantic at lists.vcfed.org
>>>     <mailto:vcf-midatlantic at lists.vcfed.org>
>>>     >>>> <mailto:vcf-midatlantic at lists.vcfed.org
>>>     <mailto:vcf-midatlantic at lists.vcfed.org>>
>>>     >>>> *Cc:* Jonathan Gevaryahu
>>>     >>>> *Subject:* [vcf-midatlantic] Working Tandy 1000 or 2000
>>>     >>>> Does VCF have a working Tandy 1000 or 2000 on display or in
>>>     the
>>>     >>>> warehouse?
>>>     >>>>
>>>     >>>> I need someone with access to a working Tandy 1000/2000 to
>>>     do some
>>>     >>>> poking from basic of the sound chip, since there's an issue
>>>     I'm
>>>     >>>> running
>>>     >>>> into with a possible incompatibility of the Tandy 1000/2000
>>>     NCR8496
>>>     >>>> PSG
>>>     >>>> (sound chip) and the more common SN76489/SN76496 PSG which the
>>>     >>>> colecovision etc used.
>>>     >>>>
>>>     >>>> -- 
>>>
>>
>> -- 
>> Jonathan Gevaryahu
>> jgevaryahu at gmail.com  <mailto:jgevaryahu at gmail.com>
>> jgevaryahu at hotmail.com  <mailto:jgevaryahu at hotmail.com>
>
>
> -- 
> Jonathan Gevaryahu
> jgevaryahu at gmail.com  <mailto:jgevaryahu at gmail.com>
> jgevaryahu at hotmail.com  <mailto:jgevaryahu at hotmail.com>


-- 
Jonathan Gevaryahu
jgevaryahu at gmail.com
jgevaryahu at hotmail.com

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