Hi Jeff and everyone,
I have a set of questions about the HxC Floppy Emulator software. I apologise if they have been answered elsewhere, but I couldn't find any answer anywhere. Please bear with me.
1. In track view mode, I reckon that the blue line above shows index pulses, while a red band just below that means a flakey/non-flux area, right?
But what is represented on the Y axis? There are more or less horizontal jagged grey lines on a microsecond scale, but I can't figure out what they are. Right clicking on track view seems to add more grey pixels, that occasionally break data encoding.
2. How long is a cell exactly? The SCP format doc says it's a set of 16 or 8 bits, but in HxC it seems way smaller than that. For example, I have a disk image with 102092 cells per track at 300 rpm, which translates into a cell time of slightly less than 2 us.
3. I can't find any documentation about the track editing tool. I think I more or less got most of it, but there are a few obscure functions/behaviours and, once again, I couldn't find a manual.
- What does Shift Tracks do? I guess it's like Shift but applies to all tracks simultaneously, right? What I don't get is why it sems to shift tracks by a number of cells equal to 104 times the number written in the box to the right.
- What does Rapair do?
- What does direct edition do?
Thanks in advance for any explanation.
Best,
Radiorama
Questions about HxC software
Re: Questions about HxC software
yes
These are the data pulses coming from the drive. At each magnetic flux reversal a pulse is generated by the drive.
(See https://www.youtube.com/watch?v=DdMOGvKjrfk)
This depend : An MFM HD / 500Kbits disk have 2 us, 3us and 4us pulse. Take the minimum value (2us in this case) and divide it by two to have the cell period (1us). Note : The software is working internally on a 250MHz bitstream to analyse the dump (the streams are upscaled at the importation/loading).Radiorama wrote: ↑Mon Jan 18, 2021 10:43 am 2. How long is a cell exactly? The SCP format doc says it's a set of 16 or 8 bits, but in HxC it seems way smaller than that. For example, I have a disk image with 102092 cells per track at 300 rpm, which translates into a cell time of slightly less than 2 us.
Yes this rotate the track. The value is in "per-thousand" of the tracks lenght. (This will probably change in a next version).Radiorama wrote: ↑Mon Jan 18, 2021 10:43 am 3. I can't find any documentation about the track editing tool. I think I more or less got most of it, but there are a few obscure functions/behaviours and, once again, I couldn't find a manual.
- What does Shift Tracks do? I guess it's like Shift but applies to all tracks simultaneously, right? What I don't get is why it sems to shift tracks by a number of cells equal to 104 times the number written in the box to the right.
This is a "brute force" feature to try to fix a sector. All the cells combinations between the 2 markers are tried until a good crc / checksum is found. Don't expect to be able to fix an heavily damaged sector with this... But this is working pretty good to fix a spot in a sector (Max window size of ~24 cells).
It allows you to manually set/clear cells. (This is what you have done : <<Right clicking on track view seems to add more grey pixels, that occasionally break data encoding.>>
Re: Questions about HxC software
Wow, really a very comprehensive reply! Thanks Jeff!
And now for the really dumb question: what does HxC stand for? Hardcore, perhaps? But why?
Best,
Radiorama
And now for the really dumb question: what does HxC stand for? Hardcore, perhaps? But why?
Best,
Radiorama
Re: Questions about HxC software
Yes exactly. This is a 23/24 years old story. HxC was the name chosen with some friends to make an hacker/cracker/demo group... I just still use it .
Re: Questions about HxC software
Last question, I promise
What does the number in the box under the Direct edition button do? The default is 010, but I can't see any difference in behaviour when I change it.
Thanks, the more I use it, the more pieces fall into place, the more I appreciate how powerful this program is.
-- R
What does the number in the box under the Direct edition button do? The default is 010, but I can't see any difference in behaviour when I change it.
Thanks, the more I use it, the more pieces fall into place, the more I appreciate how powerful this program is.
-- R