Too bad H5 is dead; the other four can all be 2716s. There's no easy way to use 2716s there and you can't easily replace one 2716 with a 2532, but you can replace a pair ;-) If you have three 2532s, program 4K images C000-CFFF, D000-DFFF and F000-FFFF into the 2532s and insert them in H1, 2 and 4 respectively, with a 2716 containing E000-E7FF in H3. Leave H5, 6 and 7 empty. You could even upgrade to BASIC2 while you're at it with the 901465-1/2/3 and 901447-24 ROM images. If you look at the schematic you'll see that each pair of low and high ROM sockets are wired exactly the same; the low 2316 is selected when pin 18 is low and the high one when it's high, and a 2532 essentially combines them with high and low on pin 18 (A11) selecting the high and low 2K halves. Maybe the VCF forum might have been a better place for this; don't know if anyone else is interested. As always, take my advice at your own risk ;-) Good luck; fingers crossed. mike ----- Original Message ----- From: "Philip Lord" <random6000@mac.com> To: <cbm-hackers@musoftware.de> Sent: Saturday, May 14, 2011 4:12 AM Subject: Re: PET 2001 fix Part 3 - RAM/ROM board etc. Me again, I have built the adaptor to read the 2316 H5, H6 and H7 into my burner using the 2K resistor. It seemed to work fine. Now I have a complete list of which ROMs work and which are dead (compared to the 901447 set from Zimmers): H1- DEAD (00's) H2- ok H3- DEAD (FF's) H4- ok H5- DEAD (every alternate second back of 128k is 00's, every alternate first bank has code but doesn't match 901447-02 at all) H6- ok H7- ok (unfortunately one of the pins completely broke off due to corrosion and I had built a make shift fix for it, super ugly but works for testing until I can get the Nicolas's RAM ROM card fixed) So three dead ROMs and one damaged (that sucks). I can burn 2716's for H1 and H3, but I'll probably need to build an adaptor for a 2716 at H5. Do I make the adaptor similar to the programmer adaptor you described, but connect pin 18 to GND instead of VCC? I also forgot to answer you question about 2532's. I do have some 2532's (and some 2732's I think) and my burner can program them. Why is it possible to use these as H5, H6, and H7 replacements if the code is doubled? Is the 2532 pin 18 active high? Doing a little bit of googling seems to suggest so. I'll do some more research. Cheers Phil On May 14, 2011, at 4:21 AM, MikeS wrote: > If you have a spare 24pin IC socket, bend out pin 18 to isolate it and put > it between the 2316 and your programmer socket, and you might be able to > read the H5 - H7 ROMs that way; if not, try connecting that 2K resistor > between the bent-out pin 18 and pin 24. > > Pleasant dreams ;-) > > m > > ----- Original Message ----- From: "MikeS" <dm561@torfree.net> > To: <cbm-hackers@musoftware.de> > Sent: Friday, May 13, 2011 3:06 PM > Subject: Re: PET 2001 fix Part 3 - RAM/ROM board etc. > > >> The ROM numbers and locations look good, but I would expect H1 to H4 to >> all >> read OK. Why not try putting your respective 2716 equivalents into H1 and >> H3, leaving the originals in H2, 4, 5, 6 and 7. >> >> BTW, can you program 2532s and do you have any? >> >> m >> >> ******************* >> >> ----- Original Message ----- From: "Philip Lord" <random6000@mac.com> >> To: <cbm-hackers@musoftware.de> >> Sent: Friday, May 13, 2011 2:39 PM >> Subject: Re: PET 2001 fix Part 3 - RAM/ROM board etc. >> >> >> Don't worry, I'm not insulted at all. >> >> I believe I have the following ROM set (I'll double check in the >> morning): >> >> Location Part Number >> ------------------------------ >> H1 901447-09 >> H2 901447-03 >> H3 901447-05 >> H4 901447-06 >> H5 901447-02 >> H6 901447-04 >> H7 901447-07 >> >> And I have followed the above convention for placement. 09, 03, 05, 06, >> 02, >> 04 and 07 in that order. >> >> When I read the original ROMs in my burner I got the following: >> >> H1 - full of 00's >> H2 - good >> H3 - full of FF's >> H4 - good >> H5 - full of FF's >> H6 - full of FF's >> H7 - full of FF's >> >> so is it possible that H5, H6, ad H7 were not read correctly by my >> programmer. H3 also shows full FF's, but H1 read as full 00's...Could it >> be >> that H1 is the only one that is indeed dead? >> >> I'll remove the two 6520 PIAs, and I'll take a look on VCF for the >> voltages >> thread. >> >> Thanks again for your time. >> >> Phil >> >> On May 14, 2011, at 3:17 AM, MikeS wrote: >> >>> Sorry, emails crossed and you answered my question before I asked it ;-) >>> >>> A crude way would be to measure the voltage on the various 6502 pins, >>> especially the Reset, Sync and Ready pins. >>> >>> There's a thread on VCF right now that might be relevant. >>> >>> m >>> >>> ----- Original Message ----- From: "Philip Lord" <random6000@mac.com> >>> To: <cbm-hackers@musoftware.de> >>> Sent: Friday, May 13, 2011 1:55 PM >>> Subject: Re: PET 2001 fix Part 3 - RAM/ROM board etc. >>> >>> >>> Thanks André, >>> I only have limited tools. Logic probe, eprom burner and multimeter. >>> >>> I'll have to snag the keyboard out of my working pet to try the 'LOAD' >>> test. >>> What other ways can I test if the CPU is working? >>> >>> Phil >>> >>> >>> On May 14, 2011, at 2:39 AM, André Fachat wrote: >>> >>>> >>>> >>>> Looking at the further discussion, you are concentrating on the video >>>> part, but is the CPU actually running ok? I didn't see that, may be I >>>> overlooked it. But you mentioned burning new ROMs as the original ones >>>> were dead. >>>> >>>> If the cpu is not running ok, this could explain the random characters >>>> on >>>> one side and also the "snow", as some random code would not wait for >>>> the >>>> vertical retrace when writing to the screen memory. >>>> >>>> Did you try checking for example with a tape and typing LOAD and >>>> pressing >>>> the Play button that the tape starts turning? >>>> >>>> I'd concentrate finding why the CPU isn't working and looking at the >>>> video later. >>>> >>>> André >>>> >>>> >>>> -------- Original-Nachricht -------- >>>>> Datum: Fri, 13 May 2011 19:27:34 +0200 >>>>> Von: "André Fachat" <afachat@gmx.de> >>>>> An: cbm-hackers@musoftware.de >>>>> Betreff: Re: PET 2001 fix Part 3 - RAM/ROM board etc. >>>> >>>>> >>>>> -------- Original-Nachricht -------- >>>>> >>>>>> So now I have a screen of random and slightly deformed characters >>>>>> (seems >>>>>> like the same or similar character layout on each start up though), >>>>>> with >>>>> a >>>>>> pixel flicker through them. I've put pics and a short video up on the >>>>> same >>>>>> page here: >>>>> >>>>> Sorry to chime in so late only. The pixel flicker might be from the >>>>> fact >>>>> that the CPU accesses the video RAM. The oldest PETs had video RAM >>>>> with >>>>> max >>>>> 1MHz operation only, so when the CPU accesses the video RAM the video >>>>> display presented "snow". The CPU controlled access to the video RAM >>>>> by >>>>> sampling >>>>> the vertical retrace on a VIA pin (VIA Port B ($e840, 59456), bit 5). >>>>> This >>>>> could relate to the fact that characters seem stable when the machine >>>>> resets (switching off?) >>>>> >>>>> Maybe the VIA has a problem here? >>>>> >>>>> On a side note: the fact that switching this vertical retrace off >>>>> resulted >>>>> snow, but also faster screen output - no wait anymore - a certain POKE >>>>> was >>>>> found to make that VIA input pin an output - accidentally destroying >>>>> some >>>>> newer models, the "killer poke". >>>>> >>>>> André >>>>> >>>>> -- >>>>> NEU: FreePhone - kostenlos mobil telefonieren und surfen! >>>>> Jetzt informieren: http://www.gmx.net/de/go/freephone >>>>> >>>>> Message was sent through the cbm-hackers mailing list >>>> >>>> -- >>>> Empfehlen Sie GMX DSL Ihren Freunden und Bekannten und wir >>>> belohnen Sie mit bis zu 50,- Euro! https://freundschaftswerbung.gmx.de >>>> >>>> Message was sent through the cbm-hackers mailing list >>> >>> >>> Message was sent through the cbm-hackers mailing list >>> >>> Message was sent through the cbm-hackers mailing list >> >> >> Message was sent through the cbm-hackers mailing list >> >> >> Message was sent through the cbm-hackers mailing list > > > Message was sent through the cbm-hackers mailing list Message was sent through the cbm-hackers mailing list Message was sent through the cbm-hackers mailing listReceived on 2011-05-14 10:00:12
Archive generated by hypermail 2.2.0.