Re: 264/TED/Plus4 Story

From: Gerrit Heitsch <>
Date: Thu, 25 Aug 2011 18:26:51 +0200
Message-ID: <>
On 08/25/2011 02:05 AM, Bil Herd wrote:

>> This design, even with the 6529 added caused me some confusion back
>> then. I couldn't understand at first why the 2 joystick ports were wired
>> n parallel and how the system was able to distinguish between them
>> until I noticed that instead of GND they used a bufferd data line (D1
>> and D2 if I remember right). This had the sideeffect that joysticks with
>> built in auto-fire never worked right on a 264.
> We tried to label the case Joy 0 and Joy 1 to match Terry Ryans beliefe that
> the function calls should be joy(0), joy(1) and we almost made it through,
> they caught it at the last moment.

Only on the C16 and C116, there the ports are labeled 'Joy 1' and Joy 
2'. On the Plus/4 they are labeled 'Joy 0' and 'Joy 1'. Adds a nice bit 
of confusion if a game wants the joystick in Port 1...

> Same time easter eggs get inserted.

You mean the SYS52650-easter egg? :)

>> schematic. I have seen other MOS-TTLs... Did MOS make those to tide over
>> shortages? But why not label them 74xxx?
> Yes and because they were in no way compatible with all of the specs. :)

Ok, that explains it... Those chips also have the reputation to die 
faster than normal TTLs.

> The 364 was kinda cool though, hired the TI Speak and Spell guys to make it
> talk.

I think it stretched the design a bit too much. Still, the PLA produces 
the select signal for it which can be abused for other I/O projects. :)

>> The 6567 before R7 were that bad? Since I live in PAL land I have never
>> seen them and the 6569R3 and later always produced a very good picture
>> f the Monitor was hooked up by Chroma/Luma.
> I think so, I would get blood running from my nose and a migraine that would
> last for 3 days from looking at an R5 since I recognized chroma noise for
> what it was... and static clock noise and dynamic clock noise, and luma
> ringing....

You don't want to see then what the PAL RF modulator does to the video 
signal produced by TED... After going through the modulator you find 
enough chroma on the luma signal that you no longer need a seperate 
composite. Use this as S-video and you get interesting patterns on the 
screen. :(


>    >Gerrit
> Bil
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       Message was sent through the cbm-hackers mailing list
Received on 2011-08-25 17:00:33

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