Hi, all. I’m developing DVD writing feature in embedded system. DVD recorder is connected via ATAPI. DVD recorder is panasonic(matsushita) sw-9586-c.
All I need is 1. multisession writing(ISO9660 file system) 2. erasing if possible. Purpose is archiving of file data to CD/DVD media.
Current system already have had built-in CD writing feature and it works almost perpectly with DVD±R, DVD±R DL by adding minor change in source code(no erasing feature, of course). But for DVD±RW, It looks like totally different story.
My first attempt was to write data on a new(blank) media. It works quite fine and multisession was also available.
But after doing quick erase(BLANK command with blank type = 01b), write command returned with sense code 05/64/00 ILLEGAL MODE FOR THIS TRACK. Only with full erase(BLANK command with blank type = 00b) I was able to do multisession writing like I did in CDR/RW media…
But MMC-5 says BLANK command(both full and minimal erasing) makes disc recording mode as sequential recording mode and FORMAT UNIT(format type 00h) command will make it Restricted Overwrite mode… Is it really unable to use incremental writing mode after quick erase? How can I detect whether media can accept incremental writing? (I think using GET CONFIGURATION command with feature code = 0023h may do the things…?)
It looks like FORMAT UNIT command do quite a trick with DVD-RW media. FORMAT CAPACITIES command with DVD-RW media give me some descriptors. (format type 10h, 11h, 12h, 13h, 14h, 15h for recorded media, 10h, 14h, 15h for blank media) But I don’t know how to use them. They looks like have something to do with… but- even without FORMAT UNIT command, I was able to do multisession writing. (WRITE -> SYNCHRONIZE CACHE -> CLOSE TRACK(RZONE) -> CLOSE SESSION(BORDER)… write mode of write mode page 05h set to 00h incremental writing)
My first attempt was same as above, but WRITE command returned with sense code 05/30/10 MEDIUM NOT FORMATTED. After take a short look at MMC-5, I learned DVD+RW media need to be formatted before using it. (Is it right to issue READ FORMAT CAPACITIES command to check whether disc is formatted or not? current descriptor will be returned with descriptor type = 01b for unformatted media and 10b for formatted media).
The problem is… I can’t get Next Writable Address with READ DISC INFORMATION and READ TRACK/RZONE INFORMATION command. I’m also not sure about multisession recording method of DVD+RW media(with ISO9660 file system…).
One test I did - I just force to start writing from 0 on blank(and formatted media) media, without the process of getting NWA. It worked alright, but I don’t know how to do multisession writing after completion of writing(that is, append new data(files) in ISO9660 file system format. Like I did in CDR/RW media).
What is proper sequence of DVD+RW multisession writing? (data will be appended everytime embedded system perform archiving action)
Erasing of DVD+RW only can be achieved with FORMAT UNIT command with format type 26h DVD+RW Basic Format ?