PRYNT, POKU, bad ROM or ULA in TS1000?

Discussions about Sinclair ZX80 and ZX81 Hardware
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XavSnap
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Re: PRYNT, POKU, bad ROM or ULA in TS1000?

Post by XavSnap »

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Xavier ...on the Facebook groupe : "Zx81 France"(fr)
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Andy Rea
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Re: PRYNT, POKU, bad ROM or ULA in TS1000?

Post by Andy Rea »

XavSnap wrote: Fri Sep 20, 2019 8:34 pm IR=$1E00
R= %000* 0000
(*) Where the bit B4 is set to 1.

Code: Select all

000* 0000 "("
000* 0001 ")"
000* 0010 ">"
000* 0011 "<"
000* 0100 "="
000* 0101 "+"
000* 0110 "-"
000* 0111 "*"
000* 1000 "/"
000* 1001 ";"
000* 1010 ","
000* 1011 "."
000* 1100 "0"
000* 1101 "1"
000* 1110 "2"
0001 1111 "3"
0001 0000 "("
0001 0001 ")"
0001 0010 ">"
0001 0011 "<"
0001 0100 "="
0001 0101 "+"
0001 0110 "-"
0001 0111 "*"
0001 1000 "/"
0001 1001 ";"
0001 1010 ","
0001 1011 "."
0001 1100 "0"
0001 1101 "1"
0001 1110 "2"
0001 1111 "3"
001* 0000 "K"
001* 0001 "L"
001* 0010 "M"
001* 0011 "N"
001* 0100 "O"
001* 0101 "P"
001* 0110 "Q"
001* 0111 "R"
001* 1000 "S"
001* 1001 "T"
001* 1010 "U"
001* 1011 "V"
001* 1100 "W"
001* 1101 "x"
001* 1110 "Y"
001* 1111 "Z"
0011 0000 "K"
0011 0001 "L"
0011 0010 "M"
0011 0011 "N"
0011 0100 "O"
0011 0101 "P"
0011 0110 "Q"
0011 0111 "R"
0011 1000 "S"
0011 1001 "T"
0011 1010 "U"
0011 1011 "V"
0011 1100 "W"
0011 1101 "x"
0011 1110 "Y"
0011 1111 "Z"
schema.jpg
Ah Ah.... BUT... you forgot that their is also a 3 bit line counter doing A0' A1' and A2' ( char code bit 0 becomes A3', bit 1 becomes A4' and so on )

Regards Andy
what's that Smell.... smells like fresh flux and solder fumes...
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XavSnap
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Re: PRYNT, POKU, bad ROM or ULA in TS1000?

Post by XavSnap »

:o

It's a joke? yes, may be a joke! just a joke…
:mrgreen:

… yes, it was the french PCB wiring diagram, the UK PCB is reversed. All right hands are in the left !
:evil:

Forgot the $1E offset.
Last edited by XavSnap on Sun Sep 22, 2019 6:49 pm, edited 1 time in total.
Xavier ...on the Facebook groupe : "Zx81 France"(fr)
KayBee
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Re: PRYNT, POKU, bad ROM or ULA in TS1000?

Post by KayBee »

Interesting responses, thank you. Some knowledgable folks here. ("There goes one now?" don't get that one)
Anyhoo, I will check the pins first, clean them up if necessary and report back. Funny, my primary TS1000 has been completely trouble free (knocks on wood).

Cheers,

KB
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1024MAK
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Re: PRYNT, POKU, bad ROM or ULA in TS1000?

Post by 1024MAK »

TMAOne wrote: Fri Sep 20, 2019 8:19 pm See? There goes one now,...
This is a reference to a person / animal / bird / or object (for example a bus, taxi) when they / it are spotted approaching and/or passing by...

Mark
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There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb :!:
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KayBee
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Re: PRYNT, POKU, bad ROM or ULA in TS1000?

Post by KayBee »

Fixed now, looks like it was the ROM. Motherboard is a ZX-81 Rev 3, all ICs socketed.Pulled the Mostek ROM, cleaned it, re-inserted. Same as before. Inserted a Sinclair ROM removed from a very beat-up TS1000, all is good now. Incidentally, I wonder if when these machines are assembled at the factory, they are tested using the edge connector. In both "new in box" machines, the edge connectors are a a little used.

Cheers all, and thank you as always,

KB
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