Re: Can I have a CP/M Console?
Posted: 20 Oct 2015 20:46
dont you mean reconfig?
dont you mean reconfig?
The world's first? Memotech MTX Forum
No, when they were first developed, there were some 40 track single sided 3.5" floppy drives. The Opus Discovery disk drive system for the ZX Spectrum used such drives (link). But fairly soon, they were replaced by 80 track single sided 3.5" floppy drives (Atari 520 STFM computers came with this type). These were normally double density types. Then double sided drives. High Density (HD) drives followed.Crazyboss wrote:Looking at the diffirent Memotech Disk types. It seems to be quite stupid to have a 40 track 3.5" - As I know all 3.5" drives have always been 80 tracks, double sided or single sided. The MSX e.g had a 3.5" disk format single sided. 360kb and also used 3.5" double sided 720kb (which is DOS compatible).
Some drives could actually exceed 80 tracks, both 5.25" and 3.5". How many depended on the actual drive mechanism itself. But I don't think there were ever any with 96 tracks. I think you are misremembering the number, as it was the tracks per inch figure (TPI), not the total number of tracks used.Crazyboss wrote:I think 5.25 drives could be 40 and 80 tracks, I also saw at least one diskdrive which was 96 tracks? maybe it was something special?
Reliability of a disk with a greater number of sectors than normal very much depends on the disk drive being able to spin the disk at the same rate as the drive that formatted the disk. Too much of a difference in speed will result in the controller accessing the wrong part of the disk surface. If it is a write operation, it's likely that the existing data will be corrupted.Crazyboss wrote:The MSX uses 512 bytes per sector and 9 sectors per track. both for the 360/720kb format. It seems to be stable, I still have MSX diskettes which is read without any errors. The Amiga used 11 sectors per track, gives around 880kb on a diskette, I have alot of problems reading those diskettes now.
This practice is not recommended (as explained by Dave). Especially with pre-formatted disks (e.g. 'IBM' formatted). The disk can become unreadable within days/weeks. However, there have been reports that if you completely erase the whole disk with a disk erasure tool (a box with a strong magnetic field) or use a (rare) unformatted disk, it's more reliable.Crazyboss wrote:By the way, people said if you downgrade a HD diskette (1.44 Floppy) to a DD diskette by covering the HD hole. Its still not good, I never had problems, but some people around the retro computers forums said it will not keep the data as secure as a true DD diskette.
Some older computers can be modified to read/write HD disks. The thing to remember is that the data rate for a HD disk is double that of a DD disk. Some Atari ST/STF/STFM/STE computers can be modified (I've done one of mine). In general, it's the floppy disk controller (FDC) system that needs to be modified. Some 8 bit CPUs however may not have the memory bandwidth to keep up.Crazyboss wrote:I am not sure if the SDX could be hacked to read and write 1.44 floppys, but I remember a quite Clever MSX guy tried to make the MSX do it back then, he said the CPU was not fast enought to do it. MSX used Z80 clocked at 3.57mhz, I think he got something to work using a Z80B at 6mhz. But its 25 years ago now
You could load the SD Card image into Silicon Disc, and then access that.I used fullcpm.bat to mount two type 07 floppy images, that works ok, but it seems like its not possible to mount a SD image as the second floppydrive?
It refuse to let me config C:18