Posted By
MikeZ
on 2009-03-31
11:48:49
 |  .d64 formatting
I created an empty file 174848 bytes long. I used Yape to format it. I looked at it again in a hex editor. You can see the directory at relative address $16500 = 357 blocks from the beginning. You can see an ID mark $4b at the boundary between each two blocks everywhere BEGINNING at relative address $1500. QUESTION FOR SOMEONE: WHY NO
BLOCK ID MARKS FOR LOCATIONS $0000 TO $1400?? Thanks.
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Posted By
BushRat
on 2009-04-12
20:48:48
| Re: .d64 formatting
No reply on this? I don't know if Joe Forster (star commander) is still around.. he really became the expert on drive format issues. I remembered the drive compatability with the 4040/1541's.. when Commodore upgraded the drive Roms to version5 (901229-05) they made and additional change in the Rom released for the SX-64. At location $f58d, in the SX, they allowed a header gap (the number of bytes between the block Id and the block sync marks) of 09 instead of 08. This was the major incompatibillity in the write situation in their drive type transition. The SX drive rom is fully compatible with the 4040 format. There was talk of changes between the 1541 and 1541II, as a matter of "production economy" and compatibility with some of the cloned 3rd party drives. I remember having to reburn one of my early Jiffy Roms, with the changes in it to get it to work right.
This might be old hat to some, but I ran into it when getting ready to tackle a fastloader for the Plus4, before I found the Euro gang already had them ( see what isolation in Alaska does). Why Commodore put the changes in some Roms and not others... is one of those Westchester divine mysteries..
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Posted By
MikeZ
on 2009-04-13
11:59:26
| Re: .d64 formatting
Hi Jim and thanks for the comment. All I wanted to know is why, when YAPE is used to format, the character "$4b" occurs ever 256 bytes except for track 1. Gaia was kind enough to give me a response. I'm not sure I understood his answer but basically he said that the "$4b" character was an artifact and didn't mean anything. I suppose I could edit out all the "$4b" characters on a newly formatted disk and see what happens when I save or load.
BTW: Back in 1987 I wrote a fast loader for the plus4. I adapted one written for the C64 that was published in COMPUTE! magazine. It was a two bit parallel use of the serial bus and depended on counting machine cycles in the plus4 and 1541 so everything lined up at the bottom of the send/receive loop. I guess it was a form of synchronous transmission.
I wrote to COMPUTE! and told them what I had done. They said there wasn't enough interest to print it. I asked them to let me put it into the PD. No dice - they wanted $200. So I sent it to Dave Johnson at Pacific Tri Micro (Plus4 Exchange).
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Posted By
BushRat
on 2009-04-13
13:29:52
| Re: .d64 formatting
Oops... should have thought of Gaia...
Yeah I;d run across some notes on the subject I'd had in the archived stuff I uploaded. On format structure, Rel and Geos formats and interleave. Glad you had gotten an answer.
That is a neat note about your fast loader. Did you ever get it out there? I got about the same kind of thing from compute, on other stuff and Trimicro just sent me a bunch of the Exchange newsletters. But heck, it was fun..
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Posted By
BushRat
on 2009-04-13
13:42:52
| Re: .d64 formatting
Yeah, it in 1988 that I was looking at loader routines.. so you were a year ahead...
I had a SuperSnapshot cart fir my C64 and was looking at some of the SpeedDos stuff, for maybe the Plus4. See what I mean about living in isolation, with the Plus4, in the States!
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Posted By
MikeZ
on 2009-04-13
14:03:18
| Re: .d64 formatting
Bringing back memories. We really were isolated - just a BBS or two. When parts started to go there wasn't any ebay and you were S.O.L. I bought 4 plus4s thinking I had plenty of spares, but the TED went bad in three of them!
I had several phone conversations with Dave Johnson about how he wrote the 3 plus 1 software. They were scrambling just like the rest of us. I also knew Fred Bowen at Commodore fairly well. He and I tinkered with hooking two plus4s back to back at the 6529 8 bit parallel port. It actually worked! About the only thing that worked really well that I got into the PD was xmodem for the plus4. Cheers...
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Posted By
BushRat
on 2009-04-13
16:42:05
| Re: .d64 formatting
Small world.. thought the xmodem thing rang a bell. Nice job, I used it. Bob Hathaway, at the local Anchorage Commodore Users Group, allowed us to put up a Plus4 subsection. At that time everything ouside of Anchorage was long distance, for us. So the Plus4 was a blessing. Replaced the 1.8mhz xtal with a faster multiple and was able to hit 19.2k baud with a modified std ibm modem. Wrote an article about the mods. The acia chip was was once tested at 115k baud, by Dave Cook down in Texas, with the proper xtal. Anyway there is a rewrite of your xmodem program out there somewhere. Was still fun, anyway
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Posted By
BushRat
on 2009-04-13
17:33:16
| Re: .d64 formatting
Thanks Mike for jogging the memory.. I'll stop here and not clutter up another thread.
I think it was Gary Vangelder that used your routine in Plusterm, wasn't it? You worked out the irq wedge, too. I he'd used George's (Hug) assembler. Our crappy phone lines here wouldn't handle the higher baudrate too well. Still made the C64 and 128 users at
the club turn green.. they could push 9600 on a sunny day with a good tale wind. Ha!
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Posted By
MikeZ
on 2009-04-14
08:28:06
| Re: .d64 formatting
Jim, Tried to find you in the members list so I could send you a private message. No luck. Is there an email address I could reach you at?
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Posted By
Chicken
on 2009-04-14
13:04:51
 | Re: .d64 formatting
Hi Jim,
you are not cluttering up anything. Quite the opposite, this is exactly the place to share your experiences. You don't get to read these things anywhere else and I'm sure I'm not the only one who followed this thread.
I think Solder exchanged the x-tal in his plus/4, too. There might be some info in the Hardware section here.
For us "Euro guys" it's also interesting to read about what was going on in the US plus/4 "scene". So just keep on writing 
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Posted By
BushRat
on 2009-04-14
20:33:00
| Re: .d64 formatting
I'm sure he played with the chips, too. Do I rememer a modem program he worked on?
Mike, I sent you an email.. bounced is your box still the one in your profile?
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Posted By
BushRat
on 2009-04-14
20:40:05
| Re: .d64 formatting
My bad! I left off a number... sent again
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Posted By
Csabo
on 2009-04-15
16:22:36
| Re: .d64 formatting
Gaia should have publicly replied to this question.  I also get a minus point for not replying myself: when I read it, I looked at a D64 file in a hex editor and concluded that I have no clue why that happens. I was going to post a short note and suggest contacting Gaia as my suspicion was that this is a YAPE specific issue. But I forgot to make that post... Anyway, I'm glad it's figured out.
MikeZ, that 2 bit parallel port loader is intriguing, and so is all the other stuff and people you mentioned. I know that many of us hunt down "the old stuff" and you seem to know quite a bit, and it's from a different "scene" than ours (ie. the "European scene"). What I'm trying to say is... I for one am interested in this stuff (I'm sure others are too), and we should try to find a way of documenting it somehow in a structured form. It's just that (and I know this is getting old!) I'm doing so much already on the site and I have very little free time at the moment, and the to-do lists are just getting longer and longer... I guess one of the points I'm trying to make is: this scene, as it still exists, "comes and goes" in big chunks, sometimes weeks, months or years between activity. As long as we all know that, and don't get discouraged by occasional silences, we'll keep on prospering the long run
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Posted By
Chronos
on 2009-04-15
16:35:33
 | Re: .d64 formatting
Anyone who hacking with .d64 files:
http://www.style64.org/
Get Dirmaster by Style and be amazed! Simply the best d64 editing tool out there!
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Posted By
Gaia
on 2009-04-17
10:39:41
| Re: .d64 formatting
Jim: any chance of recovering that V364 Speech Demo disk you mentioned? And just who's the guy who had found it? Does he have an email address?
You see, I was about to convert the Magic Voice demo disk from C64 for some "native" V364 SW, but that's kind of dull being all BASIC and sprites with some SID... :-/
(and yes, Dirmaster is indeed one heck (hack?) of a tool, it's only fault is that it came 10 years too late )
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Posted By
BushRat
on 2009-04-17
18:33:25
| Re: .d64 formatting
Gaia, it's on my LOOK list. I've run across some more 1581 disks, with partitions that I'm working through. Lost a lot of stuff during the Miller's Reach forrest fire, back in '96. Also checking corespondence files. I think it was via Vander White, wih I could recal for sure. Have you checked Marco's old Funet archive?
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Posted By
Gaia
on 2009-04-19
03:05:04
| Re: .d64 formatting
Thanks, Jim. I am pretty sure it can not be found anywhere else in the whole wide world. While doing the speech emulation in 2006 I have pretty much dug up the complete internet for resources. The closest I could get was the C64 Magic Voice demo disk along with a couple of recordings and videos.
BTW, while we're at it, rumor says it, some people could get hold of the plus/4 version of Magic Desk I (and/or II), too. Version 2 was never released but did exist as demo with MV speech support.
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Posted By
BushRat
on 2009-04-19
14:02:17
| Re: .d64 formatting
Magic Desk rings a bell... may be way off base, but directory that aditional stuff I uploaded, especially the eprom and rom listings. I'll recheck, just don't have my disks handy.
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