COS310/WPS278 floppy images?

[hush]

hey all, anyone have mirrors of the above-mentioned in a gotek-friendly format? dave gesswein has some on his site but they are in rx01 format and i'm not sure how best to convert them for use on a real DECmateII. thank you

 

[Hunta]

I can convert them from rx01 format with interleaving to rx01 format without interleaving, but will this allow the target system to work with Gotek images - that is the question...

 

[hush]

i've been able to boot OS/278 from the teledisk images on ibiblio so it will boot using a gotek, i just don't currently have any secondary storage

i'd need them converted into a format flashfloppy can read, listed here: https://github.com/keirf/FlashFloppy/wiki/Image-Formats

if someone knows how i can make a second gotek work on a separate cable, i'm all ears! x)

 

[Hunta]

The bigger question here is whether there is information about the disk type in the disk image. Let's say, in FS RT-11 and RSX-11 this is not the case, but in FS DOS-11/XXDP - yes. Therefore, let's say, when creating a XXDP disk image, I NEED to specify the disk type.

 

[hush]

that i really couldn't tell you, floppy formats are something i'm not all too familiar with. the images are here if you've got the spoons to take a look: https://www.pdp8online.com/images/images/cos.shtml

 

[Hunta]

http://www.KpXX.Ru/FTP/SDf3w5t4 - without interleave

 

[hush]

no luck there, flashfloppy complains about a bad image type

 

[Hunta]

flashfloppy complains about a bad image type

What type of image is specified in flashfloppy? And what kind of drives does the target system - rx01 - expect to see?

 

[Hunta]

Perhaps the information here will help - https://github.com/keirf/FlashFloppy/issues/375 - about setting up the geometry description for rx01 - it’s good that this format has software sectors

 

[hush]

the decmate ii should (i think) be looking for rx50s and that's what my flashfloppy config is emulating, i don't think it cares what image type is loaded as long as it's supported by the flashfloppy software. IMG/DSK in IBM MFM format would probably be most universal?

 

[Hunta]

http://www.KpXX.Ru/FTP/SDf3w5t4
.rx50 - with standard interleaving, .dsk - without interleaving

 

[hush]

still no luck, though i didn't get an invalid image error this time, just the blinking floppy disk on the DECmate screen

 

[Hunta]

It looks like an image a la rx01 is expected, which means we need to try to describe the geometry in Gotek

 

[Chuck(G)]

WPS278 is RX01, I believe. Skips first track, every track thereafter is interleaved 2:1 with a track skew. At least that's what I use when converting the things. Note also, that it takes three 128 byte sectors to create 2 256 word sectors. 128*8 128*8 + 2(128*4). There's also an RX02 format, but I forget what it looks like.

DECMate II using RX50 uses 512 byte sectors, but uses only 12 out of every 16 bits in the sector. Also skewed.

 

[hush]

aha, so the flashfloppy config i'm using isn't working because it's for an rx50. it shouldn't be too hard to extend the ff.cfg i have to support another disk type

 

[shirsch]

RX50 emulation is built into Flashfloppy. Just specify host = dec.

 

[hush]

RX50 emulation is built into Flashfloppy. Just specify host = dec.

correct, but i cannot boot rx01 media because it is unsupported in firmware. i had a half-baked idea to sysgen the cos310 media to another disk earlier but since simh pdp8 cannot take an rx50 it will not work

is there anything special that needs to be done in order to make an rx50 bootable? putr supports both, maybe i could just copy/bin one disk to another?

 

[hush]

not sure that putr is happy with this disk

 

[Chuck(G)]

Well, here's the first part of an WPS278 RX50 image:

00000000  e5 e5 e5 e5 e5 e5 e5 e5  e5 e5 e5 e5 e5 e5 e5 e5  |................|
*
00001400  00 00 02 00 08 08 08 e7  00 01 00 00 00 00 00 00  |................|
00001410  00 00 ff 09 ff 09 ff 09  ff 00 28 00 31 00 21 0a  |..........(.1.!.|
00001420  2b 04 2b 0b 0e 07 2b 08  14 0a 07 04 3a 0a 44 0b  |+.+...+.....:.D.|
00001430  32 00 ed 0d 2c 0a c0 0e  ec 0d 11 0a 08 0f 11 06  |2...,...........|
00001440  1a 0b 10 02 0f 06 29 06  29 0a 2b 08 0e 07 23 0a  |......).).+...#.|
00001450  c5 0e 31 02 49 06 20 0e  07 06 01 0e 06 06 44 0b  |..1.I. .......D.|
00001460  c7 0e 49 02 e9 0d d5 0e  06 02 2b 08 06 06 c1 0e  |..I.......+.....|
00001470  2b 08 2b 08 80 00 00 01  49 02 e9 0d 15 0a 12 00  |+.+.....I.......|
00001480  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
000014e0  00 00 00 00 00 00 00 00  00 00 00 00 d4 0e b6 08  |................|
000014f0  fc 02 21 06 c5 0e b6 08  49 02 45 00 a8 0f 03 0e  |..!.....I.E.....|
00001500  03 06 fd 02 49 02 e9 0d  ed 0d 8e 0a ea 0d fe 00  |....I...........|
00001510  a8 0f de 06 03 02 49 02  49 06 ff 02 a0 0f 9e 0a  |......I.I.......|
00001520  03 02 a0 0f e3 02 e3 02  e3 02 05 06 e0 0e 07 06  |................|
00001530  be 08 08 0f 0d 07 0c 03  2b 08 a4 0a a0 0e 0c 02  |........+.......|
00001540  0c 06 07 04 a2 0a e4 04  a0 0a d5 0e b6 08 49 02  |..............I.|
00001550  e5 00 a0 0f bd 0b fb 0b  00 00 e1 02 26 0c 21 0c  |............&.!.|
00001560  b9 0a 80 0e b6 0b 00 0f  00 00 81 0e 04 06 05 02  |................|
00001570  04 0e 0a 06 0a 02 e2 02  c8 0f ca 0a 01 0e e2 02  |................|
00001580  0a 02 01 0e 06 06 c7 0e  d9 08 06 02 2b 08 80 0e  |............+...|

I have processed about a 100 of these disks, so I am familiar with the structure. Being WPS, there are no file names per se, just numbers.

 

[hush]

these steps in putr did not result in a bootable image:

> ini cos310-dmii.dsk /rx50 /os8
> mou rx0: cos310-orig.dsk /rx01 /os8
> mou rx1: cos310-dmii.dsk /rx50 /os8
> copy/dev/bin rx0: rx1:

i'm clearly missing or misunderstanding some key information here :/