GoodStuff (Was: A Sam-related post :-)
08 Jan 2002 16:50:46 + Howard Price [EMAIL PROTECTED] wrote: Okay, so it's not the most interesting news in the world, but this list is awfully quiet now, isn't it! OK. Some files has been lingering in incoming some time now. I have not moved them out because of the possible copyright infridgement with some of the files. I hope I have removed those which areplease let me know if you own the copyright for any of these files or know if they still is protected and I'll remove them before I make the rest available for download. ftp://ftp.nvg.ntnu.no/pub/sam-coupe/cw.txt -Frode -- ^ Frode Tennebø | email: [EMAIL PROTECTED] ^ | Ericsson Radar AS. | Isebakkeveien 49 | | N-1788 Halden | Phone: +47 69 21 41 47 | | with Standard.Disclaimer; use Standard.Disclaimer; |
BDOS weirdness
I was trying to write some Sam discs using the dreaded SAMDISK.EXE (and the much nicer SAMDSK.EXE) on my PC at home and they kept failing to write, writing a few tracks and then failing or failing somewhere else in the DSK file as it was written. Thinking the target discs may not be formatted I went back to my Sam and formatted them again. Same result. Then in a fit of madness I booted from a floppy instead of from my Atom and formatted a disc under SamDos. This time it worked fine, and on all subsequent discs I wrote. Now I know that BDOS formats verifies both sides before moving to the next track which is handy, but why should there be any difference in the physical format - of is it just the floppy drive in the PC is a bit too fussy? Dan. Green Flag Limited, registered in England no. 1003081 registered office The Wharf, Neville Street, Leeds LS1 4AZ. UK Insurance Limited is also a member of the Green Flag group of companies and is a member of the General Insurance Standards Council.
RE: BDOS weirdness
[EMAIL PROTECTED] wrote: Now I know that BDOS formats verifies both sides before moving to the next track which is handy, but why should there be any difference in the physical format - of is it just the floppy drive in the PC is a bit too fussy? Probably not a perfect test, but I've looked at the source for BDOS 1.5a and MasterDOS 2.3. The only difference in the physical format seems to be MasterDOS using an extra three 0x4e bytes (27 compared to 24) at the end of each sector, which it comments as more time between sectors. Might just be the PC being sensitive to that? Alternatively, could you e-mail me the version numbers of BDOS and SAMDOS? It'll be easy to stop it in the track formatting code in SimCoupé to compare the raw formats being used... Si
RE: BDOS weirdness
On Mon, 14 Jan 2002, Simon Owen wrote: [EMAIL PROTECTED] wrote: Now I know that BDOS formats verifies both sides before moving to the next track which is handy, but why should there be any difference in the physical format - of is it just the floppy drive in the PC is a bit too fussy? Probably not a perfect test, but I've looked at the source for BDOS 1.5a and MasterDOS 2.3. The only difference in the physical format seems to be MasterDOS using an extra three 0x4e bytes (27 compared to 24) at the end of each sector, which it comments as more time between sectors. Might just be the PC being sensitive to that? I haven't examined the source, but do both formats have the same track skew? I may have got that terminology wrong. What I mean is that IIRC SamDOS aligns sector 1 of track 1 with sector 2 of track 0, and continues to spiral outward. The reason for this is that after reading all the sectors of track 0, you're likely to want to read the first sector of the next track; but by the time the head has moved between tracks, the disk has spun past the point at which sector 1 would have started. By moving the sector along up to the place where the next one would have started, the head gets enough time to move and can start reading sooner, rather than waiting until the disk has gone all the way round again. I don't think MSDOS generally does this, and sometimes I've used Linux PCs which were confused unless the disk was formatted without skew. MasterDOS has a DVAR which allowed you to change the number of sectors to offset by, including zero. Andrew -- --- Andrew Collier http://mnemotech.ucam.org/ --- -- r2+ T4* cSEL dMS hEn/CBBL A4 S+*++ C$++L/mP W- a-- Vh+seT+ (Cantab) 1.1.4
SAM pieces to trade?
Hello, i'm missing a few pieces of my Sam: the plastic cover of the power supply, the white cover for the floppy and the eject plastic button of the floppy. I have also problems with the drive: the belt is broken. Is there anyone that can help me? I have a few original manuals to trade, if you are interested write me... Thanks, Bruno
spare floppy drives
hi i noticed people were talking about spare parts for the sam and thought i'd just post a little message with my request. so .. if anybody has a spare [cheap] floppy drive for the sam then i would be interested in it. i have an external one, i think it was one that datel made for the spectrum, but they used to work on the sam. [i think it was datel]. and that's broken now. so i'm always on the lookout for a new one. anyway just if anybody has a broken sam or something that they want to sell bits from. cheers rich _ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com
RE: BDOS weirdness
Andrew Collier wrote: I haven't examined the source, but do both formats have the same track skew? It seems not! SAMDOS uses a skew of 2 (or -2?), so the first track starts with sector 1, and the next track starts with sector 9, the next with 7 etc. BDOS 1.7n uses 1 (or -1) as default skew, so the second track start with sector 10, the third with sector 9, etc. Still seems odd that this would affect anything, besides making it slower/faster to read, but it's about the only difference so far. MasterDOS has a DVAR which allowed you to change the number of sectors to offset by, including zero. I couldn't see it mentioned in the BDOS DVAR values, but it'd probably still be possible to poke it into the code manually. It'll slow down the overall access to the disk on a real SAM, but that'd be a small price to pay to get them working in a PC drive! Si
Re: spare floppy drives
so .. if anybody has a spare [cheap] floppy drive for the sam then i would be interested in it. i have an external one, i think it was one that datel made for the spectrum, but they used to work on the sam. [i think it was datel]. and that's broken now. so i'm always on the lookout for a new one. If you're feeling flush you can get a shiny new one from Colin: http://www.quazar.clara.net/sam/ for under 50 quid. Dan. Green Flag Limited, registered in England no. 1003081 registered office The Wharf, Neville Street, Leeds LS1 4AZ. UK Insurance Limited is also a member of the Green Flag group of companies and is a member of the General Insurance Standards Council.
Re: SAM pieces to trade?
i'm missing a few pieces of my Sam: the plastic cover of the power supply, the white cover for the floppy and the eject plastic button of the floppy. I have also problems with the drive: the belt is broken. Is there anyone that can help me? Colin Piggott will sell you a brand new unit for UKP48, have a look at http://www.quazar.clara.net/sam/ Dan. Green Flag Limited, registered in England no. 1003081 registered office The Wharf, Neville Street, Leeds LS1 4AZ. UK Insurance Limited is also a member of the Green Flag group of companies and is a member of the General Insurance Standards Council.
Re: spare floppy drives
i noticed people were talking about spare parts for the sam and thought i'd just post a little message with my request. so .. if anybody has a spare [cheap] floppy drive for the sam then i would be interested in it. i have an external one, i think it was one that datel made for the spectrum, but they used to work on the sam. [i think it was datel]. and that's broken now. so i'm always on the lookout for a new one. Hi, As Dan has said in his reply, I sell new drives for the Sam for GBP 48, that includes the disk drive mechanism itself and interface board with the disk control circuitry, and it all fits inside the Sam like the original disk drives. Details on the main news page at http://www.quazar.clara.net/sam/ (See the news for 10th May 2001 for the disk drive systems) If you need any more info etc, then feel free to drop me an email. Colin Piggot Quazar : Hardware, Software, Spares and Repairs for the Sam For all the recent Quazar news, see the new look website: http://www.quazar.clara.net/sam/
Re: SAM pieces to trade?
i'm missing a few pieces of my Sam: the plastic cover of the power supply, the white cover for the floppy and the eject plastic button of the floppy. I have also problems with the drive: the belt is broken. Is there anyone that can help me? Colin Piggot will sell you a brand new unit for UKP48, have a look at http://www.quazar.clara.net/sam/ Dan. Cheers Dan for the second plug of the day :) Colin Piggot Quazar : Hardware, Software, Spares and Repairs for the Sam For all the recent Quazar news, see the new look website: http://www.quazar.clara.net/sam/
