Hard sector format

[Jeff]

Not surprised about the error since i convert it from a singled sided kryoflux dump

Let me convert the others images .

[Jeff]

Not surprised about the error since i convert it from a singled sided kryoflux dump

Let me convert the others images .

Here it is :

https://hxc2001.com/vrac/HS/ns_ds_new.hfe

[snhirsch]

Not surprised about the error since i convert it from a singled sided kryoflux dump

Let me convert the others images .

Heh. That would explain it! Actually my fault - when I imaged the diskette I didn't realize it was double-sided. So, some of the files had sectors on the (non-existent) second side .

That being the case, I think things are working correctly! This is very, very good news.

[snhirsch]

Not surprised about the error since i convert it from a singled sided kryoflux dump

Let me convert the others images .

Here it is :

https://hxc2001.com/vrac/HS/ns_ds_new.hfe

That's somewhat better, but I'm still getting random "NO INDEX PULSE" errors on file read or sequential surface scan. Sometimes a retry will succeed, so whatever it is is right on the edge of the acceptable timing windows.

[Jeff]

Not surprised about the error since i convert it from a singled sided kryoflux dump

Let me convert the others images .

Here it is :

https://hxc2001.com/vrac/HS/ns_ds_new.hfe

That's somewhat better, but I'm still getting random "NO INDEX PULSE" errors on file read or sequential surface scan. Sometimes a retry will succeed, so whatever it is is right on the edge of the acceptable timing windows.

"NO INDEX PULSE" mean no rotational index or no sector index or both ?

[snhirsch]

Here it is :

https://hxc2001.com/vrac/HS/ns_ds_new.hfe

That's somewhat better, but I'm still getting random "NO INDEX PULSE" errors on file read or sequential surface scan. Sometimes a retry will succeed, so whatever it is is right on the edge of the acceptable timing windows.

"NO INDEX PULSE" mean no rotational index or no sector index or both ?

Here's the explanation in the manual:

Code: Select all

4 NO INDEX PULSE
Indicates that the wrong type of diskette or a badly seated diskette was present.

I interpret that to mean it didn't find a sector index pulse where it expected to. For example, sector is shifted late such that controller is still processing the data field or CRC at the time the pulse arrives. By the time the controller state-machine finishes the data phase and starts looking for the sector index, it's already gone by. But, this is just a guess since I do not have the diskette driver source code.

It's worth recalling Mark Garlanger's experience with Heath diskettes. Data always started a bit earlier than the specs suggested. Perhaps the N* preamble of zeroes is starting too late? 96usec. is nominal, not min.

[Jeff]

Ok, preamble extended :

Let me know if this help or not :


https://hxc2001.com/vrac/HS/ns_ds_new.hfe
https://hxc2001.com/vrac/HS/ns_ds_kf.hfe

[snhirsch]

Ok, preamble extended :

Let me know if this help or not :


https://hxc2001.com/vrac/HS/ns_ds_new.hfe
https://hxc2001.com/vrac/HS/ns_ds_kf.hfe

I think you misunderstood me. My point was that the preamble (33 zero bytes) may have to start sooner after index. The latest images do not read at all. Immediate error on access to anything.

[Jeff]

ok , images updated :

https://hxc2001.com/vrac/HS/ns_ds_new.hfe
https://hxc2001.com/vrac/HS/ns_ds_kf.hfe

[snhirsch]

Now I have hardware problems here. The activity LED on the Gotek no longer lights up and none of the images work. I'll try reflashing the firmware tonight. If that doesn't work, I think I have another Gotek with your bootloader to try.

[Jeff]

Now I have hardware problems here. The activity LED on the Gotek no longer lights up and none of the images work. I'll try reflashing the firmware tonight. If that doesn't work, I think I have another Gotek with your bootloader to try.

The green led/activity led is directly connected to the DS0/DS1 Floppy bus (no firmware/software drive this led). So if this led doesn't work, the problem is probably more in the machine itself... , unless the the gotek 3.3V is gone... but this doesn't seem to be the case here since you can select the images.

[snhirsch]

Now I have hardware problems here. The activity LED on the Gotek no longer lights up and none of the images work. I'll try reflashing the firmware tonight. If that doesn't work, I think I have another Gotek with your bootloader to try.

The green led/activity led is directly connected to the DS0/DS1 Floppy bus (no firmware/software drive this led). So if this led doesn't work, the problem is probably more in the machine itself... , unless the the gotek 3.3V is gone... but this doesn't seem to be the case here since you can select the images.

Yes, it is possible I have cabling issues. Ran out of time before my "real" work (the kind that pays) started . Will straighten it out tonight.

[snhirsch]

It was a bad 34-pin cable. With a new cable, those latest images read almost perfectly. On the double-sided image, I consistently get read errors on sector 342 and 600. Error is "NO INDEX PULSE". Do you see anything odd with the data or timing on those sectors? The original diskette reads fine.

The single-sided diskette also has a consistent read error on sector 342 (same error message).

I saw a couple of other random errors when doing a wildcard copy of data from the Gotek, but I do not see these on the surface scan (linear read). Wondering if there's a problem with read after seek?

I'm able to boot from the emulated drive as well.

I don't know when this cable started acting up, but it's possible that the images you sent last evening were ok. Looks like you're continually overwriting the ones on your server, so I cannot go back to check.

Again, let me thank you for your efforts. This is definitely good progress and I'm sure you'll figure out the remaining issues.

[Jeff]

Ok here all the tests images :

https://hxc2001.com/vrac/HS/tests/

Let me know what work and what doesn't.

About the sectors 342 & 600 i am not sure where they are located on the disk (at which track/side ?). It look like these sectors are "empty", but i am not sure which track/side to look.

Btw is there a some raw sectors images available ? I have created some ".NST" raw file from the kryoflux dump, but i want to make the hxc software input/output compatible with existing raw file for Northstar... (If this format is already existing...)

[snhirsch]

Ok here all the tests images :

https://hxc2001.com/vrac/HS/tests/

Let me know what work and what doesn't.

About the sectors 342 & 600 i am not sure where they are located on the disk (at which track/side ?). It look like these sectors are "empty", but i am not sure which track/side to look.

Btw is there a some raw sectors images available ? I have created some ".NST" raw file from the kryoflux dump, but i want to make the hxc software input/output compatible with existing raw file for Northstar... (If this format is already existing...)

The disks are written with 10 sectors per track, 35 tracks per side. Sides are handled in a serpentine manner, tracks 0-34 on side 0, then 34-0 on side 1. Many older formats use this arrangement, since it saves a full disk seek on files that straddle sides. Sector numbering starts at 0. So, sector 342 is "track 34, sector 2 (side 0)". The first sector on side 1 is 350 (track 34, sector 0, side 1). So, sector 600 lies 250 sectors - or 25 tracks - out towards the edge of the diskette. 34 - 25 = 9, so it looks like sector 600 is physically "track 9, sector 0" on side 1. Hopefully this makes the layout clear.

There should be no "empty" sectors. Low level format writes every sector on the diskette. The surface scan tool (built into the Northstart 'copy' program) reads every sector sequentially. The original diskette reports NO bad sectors so they must all be readable by the diskette controller.

I will send some "official" NSI images to the ftp upload directory. As I mentioned in a note last week, these are simply sector data in a linear arrangement. You will need to keep the serpentine ordering (as describe above) in mind when organizing the double-sided NSI into HFE images.