DOS ain't dead - Panasonic CF-51, USB Devices in Real-Mode

Brian_extended

30.08.2016, 01:09

Panasonic CF-51, USB Devices in Real-Mode (Announce)

Maybe old news for everyone, but new to me.

I just picked up Three Panasonic CF-51 Toughbooks, loaded "Dos 7.1" (Win98se realmode) and XP SP2. Booting into real-mode DOS supports USB memory sticks and devices, including CF cards and SD cards using a reader. Boot off the USB, floppy, or hard drive. I can read SD cards direct from the camera, and load programs directly to the cards for use on embedded systems. 2Ghz processor, 1GByte memory- runs all of my extended mode Microway compilers and Phar Lap DOS extenders. Makes it easier to write to a bootable SD or CF card for my embedded systems.

$150 for all three, seem to go for less than the CF-50. I bought 3.5" floppies for the MP bay, but USB floppy support also works under real-mode.The CF-50 does not have real-mode support for the USB, and the CF-52 went to SATA hard drives. I have those as well, the CF-52 was free. The latter boots and runs off a USB device in real mode, the SATA hard drive is more of an issue.

Brian_extended

05.09.2016, 14:19

@ Brian_extended

Panasonic CF-51, USB Devices in Real-Mode

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A follow-up, and solved an old mystery for me.

Most of the computers used over (almost) 20 years: DOS 7.1 (Win95B, win98,win98se) booted into realmode have no problem handling more than 64MBytes of memory. The Panasonic CF-50- loaded with 1GByte, no problem using all memory with Phar Lap extenders.

The CF-51: I had to load HIMEM.SYS to use memory above 64MBytes. Maybe Phoenix BIOS reverted back to an older version of DPMI when implementing native USB support?

HIMEM.SYS and Phar Lap "get along", so my image processing code is working again on the CF-51.

Brian_extended

17.09.2016, 22:40

@ Brian_extended

Panasonic CF-51, USB Devices in Real-Mode

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I have two Panasonic CF-52's, "repurposed" for whatever I want to do with them. These use SATA drives, I wanted to use one as a DOS computer bootable with the hard-drive. This took a lot of trial and error, turns out using Partitions on the SATA drive "screwed up something". The machine just would not boot from the hard drive, but booting off USB stick would work- partitions all worked.

I was able to make a bootable SATA drive by using the entire drive as the primary DOS partition, set active, formatted FAT-32.

FreeDOS 1.1 ISO bootable CD worked;
FDISK with FreeDOS worked- made a Single Active partition using 100% of the drive;
FORMAT with FreeDOS "did not quite work", had write errors in doing copies to the drive.

SO: Made a Bootable USB Stick with HP's USB utility with WIN98se booted into Realmode with BootGui=0;
Used FORMAT.COM with FORMAT C:/s to install DOS.

This worked. Using FDISK with either FreeDOS or Win98 to make multiple partitions somehow prevented the disk from being bootable.
Used the oakcdrom.sys mscdex.exe that came on the FreeDOS distro with the "DOS 7.1" config.sys and autoexec.bat. Needed to load HIMEM.SYS for the system to see memory above 64MBytes on the CF-52, now at 512MBytes and can go higher. I have a CF-50 running DOS with 1.5GBytes. I use DOS Extenders for embedded systems; the tools and software can all be written, compiled, and tested on these computers that ran under $100 each.

The Panasonic CF-51 and CF-52 have native support for USB built into the BIOS, so USB storage devices and USB floppy are all mapped as DOS disks. The build quality spoils you.

Brian_extended

19.09.2016, 22:17

@ Brian_extended

Panasonic CF-51, USB Devices in Real-Mode

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The CF-52 with SATA 512GByte FAT-32 drive is now dual-booting DOS7.1 (win98se) and XP SP3. Used "nLite" to include the SATA drivers for the computer onto a bootable XP Install CD. Original XP installation CD's do not have SATA drivers, and do not have support for USB Floppy disks- even if the BIOS of the machine has native support for it. Once XP has loaded it's drivers, it stops seeing the USB floppy. SO for the times that this machine needs XP, it has it. I wrote a custom demosaic routine for my Leica's to run under Phar Lap DOS. Boot into XP to use Photoshop CS2.