Re: TED bug?

From: Istvan Hegedus <>
Date: Fri, 7 Nov 2014 08:48:01 +0100
Message-ID: <>
Thanks Gerrit,

Yes I only have the die shot of 8360R2 so if you could send me the 8360R1 
die shot that would be great!
I have one 8360R1 which just died recently with keyboard latch problem. Some 
keys are not working so I cannot measure its behavior anymore.

How do you stick the DIP cooler on top of the IC? Do you use a glue or just 
a heat paste? Active cooling needs some investigation because it requires a 
very small fan...


From: "Gerrit Heitsch" <>
Sent: Thursday, November 06, 2014 8:17 PM
To: <>
Subject: Re: TED bug?

> On 11/06/2014 08:04 PM, Istvan Hegedus wrote:
>> Hi,
>>> I haven't seen this problem, but may I ask why you'd want to use the
>>> STOP bit at all? If you want better than normal speed, just allow TED
>>> to double clock the CPU and disable the display. This should run the
>>> CPU on double clock all the time (except the 5 refresh cycles per
>>> scanline). You only get to see the border color though.
>> Yes I know this is better way for speeding up calculation. I don't want
>> to use TED stop just investigating how it works.
>> I am collecting information on TED for a future project...
> You've seen the die shot of a 8360R1 TED? I could mail it to you if you 
> don't have it yet. Might give you some insights.
> Also remember that 2 of the keyboard latch pins are used for testing when 
> pulled to 10V. At least that's what they were on the 7360, don't know if 
> they kept it in the 8360 so be careful.
> K0: Freeze the system, switch to single clock, DRAM refresh.
> K1: Force clock division to NTSC.
> K0 looks like the STOP bit triggered externally.
>>> If you're on a PAL system and want even better speed while not caring
>>> about the video output at all, disable the display and then switch TED
>>> to NTSC. This changes the clock divider from 10 to 8 which will run
>>> the CPU on a PAL system on about 2.2 MHz. This assumes that the rest
>>> of the system can keep up and the CPU is well cooled...
>> Good idea, I will try it after I installed DIP cooler to the CPU.
> I would also suggest some aktive cooling since the 8501-CPUs are becoming 
> increasingly rare.
> Back in 1986 I had the CPU cooled with a DIP cooler and used that trick to 
> speed up calculations by quite a bit (well, about double speed compared to 
> the standard setting of visible screen and double clocking during the 
> border)
> If you don't have them yet:
>  Gerrit
>       Message was sent through the cbm-hackers mailing list

       Message was sent through the cbm-hackers mailing list
Received on 2014-11-07 08:00:03

Archive generated by hypermail 2.2.0.