ewen@actrix.gen.nz (Ewen McNeill) (03/19/91)
In article <9g9Zy1w164w@ijpc.UUCP> ianj@ijpc.UUCP (Ian Justman) writes: > ankh@diku.dk (Klaus Ambrass) writes: > > > Well, I had that prob myself once. > > Way back then, it was due to the packing format applied by who ever packed > > the file in the first place. > > I have an Amstrad cpc6128 and found that sometimes, when you CRUNCH a > > file you can UNCR it, but not UNCRLZH it. I know it sounds loony, but the > ^^^^^^^^^^^ FALSE, FALSE, FALSE!!!!!! > > two programs are in fact different. > > (flamethrower on maximum and enjoying it!!!!) > > YOU'RE ABSOLUTELY DEAD WRONG!!!!!! > > I USE UCRLZH.COM TO UNCRUNCH ?Z? FILES ALL THE TIME!!!!!! > And YOU don't really know what you are talking about. I have had the same problems as Klaus has had -- I also own a CPC6128. The problem he describes is exactly true, for the CPC6128. There is a bug (somewhere) in the Bios. I am going to have to go reverse-engineering it (there is no Bios source available to my knowledge). FTR, I have successfully used UCRLZH to uncrunch files (.?Z?), so it definately does work. This was not off the floppy drives on the Amstrad, however (this is where the bug is). So the real answer is that you are both right.... :-) Sortof. > IF YOU WANT TO MAKE ME EAT MY WORDS, TRY IT!!! I know I'm right > about this one. I know because I've used it. Have YOU tried it? > UCRLZH11.COM _WILL_ uncrunch ?Q?, ?Z?, and ?Y? files. What you > just said is one of the biggest crocks I've ever seen! If you own an Amstrad, and you haven't had any problems, I would love to hear what you do. Otherwise, YOU don't know exactly what you are talking about. May I suggest, in future, that you don't jump in with all guns blazing (to mix metaphors), and instead find out why the person made the statement? Also, FTR, the reason that one program works (UNCR), and another doesn't (UNCRLZH), seems to be connected with the amount of register preservation they do, the amount of use they make of the extra Z80 registers, what they actually call, and a few other things. For instance, unzip (David Goodenough) doesn't work too well on the Amstrad drives for some reason. It works fine off my Ram disk (the patch for which appears to have been made (autoinstall program) at a higher level than the bug) however. [BTW, this is nothing against David's program -- it SHOULD work perfectly on the Amstrad, and does on other systems] Unarc (I forget who wrote it at the moment), on the other hand, works perfectly. I looked through the source, and saw lots of places where it used the extra registers very carefully, and preserved them all the way through (interupts off), etc. The comments mentioned problems with extra register usage on "various computers". Further information, (for those with advice rather than flames!), it appears that everytime this bug occurs the same piece of code/whatever is copied into the disk-sector buffer, rather than the sector required. Only 128 bytes long, but morethan enough to scamble anything that is supposed to be being decompressed. I discovered this when one of my editors (ZDE - I don't have any source to check what it does) had the same problem. One more little thing to note, the problem doesn't occur all the time, and as far as I can tell it happens at random. This cannot be true, but I haven't discovered what causes it yet. One possible lead is that sometimes a file will fail, and then if the operation is tried again after resetting the drives, it will work. [This is CP/M+, BTW, the drives are supposed to auto-reset when needed] Sorry, everyone, that this has got this long. It was intended to rebut the flame, but the opportunity to seek others opinion on the problem couldn't be missed. Any useful suggestions are welcomed, and any off-the-cuff flames will be dealt with in a suitable manner (ie, probably ignored!). -- Ewen McNeill. Email: ewen@actrix.gen.nz
ianj@ijpc.UUCP (Ian Justman) (03/20/91)
ewen@actrix.gen.nz (Ewen McNeill) writes: > And YOU don't really know what you are talking about. I have had the > same problems as Klaus has had -- I also own a CPC6128. The problem he > describes is exactly true, for the CPC6128. There is a bug (somewhere) > in the Bios. I am going to have to go reverse-engineering it (there is > no Bios source available to my knowledge). (stuff deleted along the way) > FTR, I have successfully used UCRLZH to uncrunch files (.?Z?), so it > definately does work. This was not off the floppy drives on the > Amstrad, however (this is where the bug is). > > Sorry, everyone, that this has got this long. It was intended to rebut > the flame, but the opportunity to seek others opinion on the problem > couldn't be missed. > > Any useful suggestions are welcomed, and any off-the-cuff flames will be > dealt with in a suitable manner (ie, probably ignored!). My deepest apologies. I guess I assumed that all BIOSes were pretty much well-behaved and it seems to be restricted to some BIOSes. Also, it probably has something to do with the fact that those computers are running CP/M Plus, which I've heard can be flakey at times. That's why I stick with my CP/M 2.2 stuff (highly uprated w/ZCPR33 and stuff like that...)
ewen@actrix.gen.nz (Ewen McNeill) (03/22/91)
[I would send this by Email, but this site (way off in NZ), doesn't know about the UUCP psuedo-domain, and just bounces the stuff. Sorry, everyone else.] In article <kFN4y1w164w@ijpc.UUCP> ianj@ijpc.UUCP (Ian Justman) writes: > [In reply to a flame rebuttal from ewen@actrix.gen.nz (Ewen McNeill)] > My deepest apologies. I guess I assumed that all BIOSes were > pretty much well-behaved and it seems to be restricted to some > BIOSes. Also, it probably has something to do with the fact that > those computers are running CP/M Plus, which I've heard can be > flakey at times. That's why I stick with my CP/M 2.2 stuff > (highly uprated w/ZCPR33 and stuff like that...) Your apology is accecpted. I have heard a fairly large number of BIOSes which have problems with various things - most written for Z80 machines in the days when 8080 code was the most common, so they assumed that they had the extra registers to themselves. This is no longer true. I doubt that the fact they are running CP/M+ has anything to do with it. CP/M+ seems okay to me, most of the time. Occassionaly it fails to relog in a disk, but that is only because of the way it detects a new disk (directory checksumming). No where near as much hassle as logging in disks under 2.2! The trouble with the Amstrad implementation of CP/M 2.2 is that they used a graphics screen (all the machine has - bit map 16K), which steals most of the useful memory. There is only about 42K TPA - hardly enough to do anything. -- Ewen McNeill. Email: ewen@actrix.gen.nz
pm@nowster.UUCP (Paul Martin) (03/23/91)
Ewen McNeill (ewen@actrix.gen.nz) wrote these words: > And YOU don't really know what you are talking about. I have had the > same problems as Klaus has had -- I also own a CPC6128. The problem he > describes is exactly true, for the CPC6128. There is a bug (somewhere) > in the Bios. I am going to have to go reverse-engineering it (there is > no Bios source available to my knowledge). Are you sure you are running the CPM+ supplied with your 6128? > For instance, unzip (David Goodenough) doesn't work too well on the Amstrad > drives for some reason. It works fine off my Ram disk (the patch for > which appears to have been made (autoinstall program) at a higher level > than the bug) however. [BTW, this is nothing against David's program -- > it SHOULD work perfectly on the Amstrad, and does on other systems] Voila! Non-standard system. I have an Amstrad CPC 464 with 512K banked RAM, and the 6128 ROM. I have used David Goodenough's UNZIP program every day for the last 9 months without a single problem, even with 200K ZIP files. I have just tried UCRLZH11 on a ?Q?, a ?Z? and a ?Y? file with no problems. May I hazard a guess that you're running ZCPR or similar, or something else non-standard? -- Paul Martin ..!uunet!tharr!pm.nowster | CP/M systems never die - they pm.nowster@tharr.uucp (pm111@tharr.uucp) | just get more BIOSed with age. <-- tharr *free* public access to Usenet in the UK -->
ewen@actrix.gen.nz (Ewen McNeill) (03/26/91)
In article <XX000000bd@nowster.UUCP> pm.nowster@tharr.uucp (Paul Martin) writes: > Ewen McNeill (ewen@actrix.gen.nz) wrote these words: > > [About certain programs not working too well for some reason on a > > Amstrad CPC6128 running CP/M+] > > Voila! Non-standard system. I have an Amstrad CPC 464 with 512K > banked RAM, and the 6128 ROM. I have used David Goodenough's > UNZIP program every day for the last 9 months without a single > problem, even with 200K ZIP files. This is depressing. Although it doesn't prove anything. However, it does sound as though there is something special about your banked ram, or something. Do you unzip things off the ram drive (I would do this anyway because it is faster -- I only discovered the problem when I had a small ram drive (one bank, instead of the usual two))? This has no problems. It is only off the floppy disks, and it needs to be a pretty big file (in another post I mentioned it happening in 15 128-byte blocks out of about 2000 in a file) for the "random" chance to happen. > May I hazard a guess that you're running ZCPR or similar, or > something else non-standard? I am running CP/M+, as supplied, with a serial interface (no special patch), and a ram disk (and the patch for it). The ram disk consists of both banks of ram, although I have had the same problem with just one bank plugged in. I think I may even have had problems without any ram plugged in, but the patch installed. The serial interface is a possibility, I guess -- who else of those with problems has a serial interface attached to their system? This does make me think of the ram patch as being the problem, so I have started to disassemble it again. If anyone is interested in helping work on this, you will need a copy of PATCHER.COM (out of the ram disk rom), and a copy of DazzleStar. I will send a copy of the DazzleStar temporary file, which defines the symbols, etc. Anyway, it is amazing how many Amstrad users there are out there. Three of us have had problems, and one hasn't. There seems to be little difference between the setups. We have, however, learnt that there is no problem with using the ram drive, but there appears to be with using the floppy drives. On a random basis. Does anyone know different? -- Ewen McNeill. Email: ewen@actrix.gen.nz