Its probably not obvious how busy we were just trying to get the damm thing to work and even then _we would have had to bump one of the other chips revision_ to rev the VIC. As it was, every day was a new emergency and then manament would make up a few more. I had 4-5 custom chips going through the cycles and two got made incorrectly in a non-usable way just over small tweaks. (The PLA shorted out its backbias ring, the MMU had its masks mixed up at MOS) My Gant chart was six pages tall, probably over 100 items on it. So counting the time to get VIC change designed, laid out, PG'ed, and a run from MOS ($$$) not that we have done without one of the other chip revs as 8563 took all slack out of the queues, there was no way we would have done something like this. To restate, I had a huge list of real problems in spite of getting fixed daily, and I wouldn't have re-decided to fix a problem that was not regarded as a problem, the trixk with going this fast is make a decision and move on, riskiest things were made less risky. Again we didn't identify any compatibility problems until we were in mass production and shipping. Also we had people canceling the real MMU, and evidently the C128D and also the LCD machine and then I left, making it smell nice wasn't an option. >:) -----Original Message----- From: email@example.com [mailto:firstname.lastname@example.org] On Behalf Of Gerrit Heitsch Sent: Tuesday, February 25, 2014 1:22 PM To: email@example.com Subject: Re: More CPLD explorations On 02/25/2014 07:07 PM, Bil Herd wrote: > Yeah I remember the 3 seconds where I made the mistake on hiding the > register in the VIC. I thought to do a "lock the door and throw away > the key" approach where only a cold start would bring it back in. Judging from the schematics, the C128 has a signal (labeled '64/128') that seems to tell some of the logic what mode it is in. That could have gotten used together with an unused pin (which it has as far as I know) on the 48pin VIC to 'disappear' the registers in C64 mode. That would also have prevented getting stuck with the registers gone in C128 mode. > But then we never said it was 100% compatible. >:) That's why I wrote 'almost'. It was still impressive. > (we had a LOT of 7406/7s) So I see... and most of them from Russia (EL74xx). Gerrit Message was sent through the cbm-hackers mailing list Message was sent through the cbm-hackers mailing listReceived on 2014-02-25 20:00:12
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