[vcf-midatlantic] Working Tandy 1000 or 2000

Jonathan Gevaryahu jgevaryahu at gmail.com
Thu Aug 30 14:21:51 EDT 2018


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>
> *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>
>     <mailto:jgevaryahu at gmail.com <mailto:jgevaryahu at gmail.com>>
>     >>>> jgevaryahu at hotmail.com <mailto:jgevaryahu at hotmail.com>
>     <mailto:jgevaryahu at hotmail.com <mailto:jgevaryahu at hotmail.com>>
>     >>>>
>     >>>
>     >>> --
>     >>> Jonathan Gevaryahu
>     >>> jgevaryahu at gmail.com <mailto:jgevaryahu at gmail.com>     <mailto:jgevaryahu at gmail.com <mailto:jgevaryahu at gmail.com>>
>     >>> jgevaryahu at hotmail.com <mailto:jgevaryahu at hotmail.com>     <mailto:jgevaryahu at hotmail.com <mailto:jgevaryahu at hotmail.com>>
>     >>
>     >>
>     >> --
>     >> Jonathan Gevaryahu
>     >> jgevaryahu at gmail.com <mailto:jgevaryahu at gmail.com>     <mailto:jgevaryahu at gmail.com <mailto:jgevaryahu at gmail.com>>
>     >> jgevaryahu at hotmail.com <mailto:jgevaryahu at hotmail.com>     <mailto:jgevaryahu at hotmail.com <mailto:jgevaryahu at hotmail.com>>
>     >
>     >
>     > --
>     > Jonathan Gevaryahu
>     > jgevaryahu at gmail.com <mailto:jgevaryahu at gmail.com>     <mailto:jgevaryahu at gmail.com <mailto:jgevaryahu at gmail.com>>
>     > jgevaryahu at hotmail.com <mailto:jgevaryahu at hotmail.com>     <mailto: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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