MSX USB | MSX Resource Center (Pagina 22/24)

Van sdsnatcher73

Prophet (3962)

17-10-2021, 20:34

MYbe try the stablr version 0.6 (from releases)? See if that behaves any different…

Van issalig

Rookie (22)

19-10-2021, 12:34

AFAIK it is not necessary to press 1. Nextor automatically detects it is a MSX1 64kb. (I have also tried pressing 1 but with the same result)
I have read that current Nextor supports it. I have built it and used those files but it does not work. Not sure if you need to recompile some of your files to include new Nextor (or maybe you are already using last version).

Wow, a full PCB is a big project, you will have a lot fun.

Van S0urceror

Master (210)

21-10-2021, 22:25

Managed to find out the problem.
When the Nextor MSXUSB driver is running in MSXDOS1 mode it expects a MSXDOS1 conformant disk.

A USB stick formatted in MacOS as FAT16 and FAT12 does not work. On a MSX2 it does.
sudo newfs_msdos -F 12 /dev/disk4

But if I copy an original MSXDOS.DSK over it, it works in MSXDOS1.
sudo dd if=MSXDOS.DSK of=/dev/disk4 bs=512

Check the result recorded in OpenMSX with my testboard.

So there is no problem with the hardware or driver. There is a problem with the disk layout not being MSX DOS 1.0 compatible.

Does anyone know what the rules are for disk formats in MSXDOS 1?
I am myself using MSXUSB on my MSX2 without issues in FAT12 or FAT16 formats.

Van Pencioner

Scribe (1565)

21-10-2021, 23:42

I think it might be related to boot sector code. My guess is that MSX-DOS2 doesn't run the routines from sector 0 while MSX-DOS1 does so the disk should be formatted from MSX which ensures sector 0 is properly initialized

Van issalig

Rookie (22)

22-10-2021, 19:02

Great @S0urceror, I was able to replicate it, I downloaded MSXDOS.DSK, copied arkanoid.com and played it. What a moment! Thanks.

But after so many experiments with cfdisk mkfs.msdos and fdisk I should have changed sth in my USB strick and now it does not work anymore.

Anyway we are on the good way.

Van issalig

Rookie (22)

23-10-2021, 11:34

A little bit more progress (USB drive works again, it was a problem of loop mounts in linux, if it happens the same to you, just reboot)

To create MSX valid disks I have downloaded dsktool from https://github.com/nataliapc/MSX_devs/

With this utility it is possible to create a 720 kb MSX disk that works

dsktool c MYDISK.DSK
dsktool a MYDISK.DSK MSXDOS.SYS COMMAND.COM
sudo dd if=MYDISK.DSK of=/dev/sda bs=512

I have also tried to use bigger disks by using
dsktool c 1440 MYDISK.DSK
but this does seem to work because 1.44Mb disk have 9 sectors per FAT while Nextor expects 3 at maximum.

From the nextor documentation it seems it is possible to create 16mb (maximum for FAT12) partitions with 3 sectors per FAT but I do NOT know exactly how to do it. oO

See doc here about this issue
"During the automatic mapping procedure, only the MSX-DOS 1 compatible partitions will be examined.
These are FAT12 partitions with three or less sectors per FAT. "
"Partitions of 16MB or less created with the built-in disk partitioning tool will have three sectors per FAT or less, so these can be used in MSX-DOS 1 mode."

Van sdsnatcher73

Prophet (3962)

23-10-2021, 15:40

You can create them by typing _fdisk in basic. Then delete your existing partitions and create a 16MB partition and write it to the disk. You can then mount this partition on PC and write files to it.

Van issalig

Rookie (22)

23-10-2021, 19:22

I tried but it does not support it (I am using a MSX1 VG8020)
It says "There are not suitable logical units available in the devices" (see images attached below)
Also it is strange that when booting v0.7 is reported but MSXUSB driver reports 0.6

For flash memory am using this file https://github.com/S0urceror/MSX-USB/blob/master/drivers/Nex... (hope it is ok)

Can someone generate a 16Mb disk image and upload it?

img1
img2
img3

Van issalig

Rookie (22)

11-11-2021, 17:13

I want to make a second unit of my msxusb but I got non working cplds (from aliexpress). Do you recommend any good source for EPM7064-SLC44-10?

Van issalig

Rookie (22)

12-11-2021, 20:29

I have been testing a bunch of USB sticks and the ones that work for me have Endpoints with this values (lsusb -v | grep bEndpointAddress)
Is it the same for you?

bEndpointAddress 0x01 EP 1 OUT
bEndpointAddress 0x82 EP 2 IN