How to boot from DOC on picoFlash?

nobody wrote on Tuesday, March 28, 2006:

Hello,

I have picoFlash with Disk-On-Chip in hand. I would like to boot FreeRTOS from Disk-On-Chip on picoFlash. Has anyone done this? Please give me some hints.

I’ve compiled FreeRTOS by using WATCOM C. I also use EXE2BIN to get the ROM code although I don’t know if the relocation segment setting(/l=0x0000) is correct or wrong. Then I program the ROM code by using dformat.exe(/win:e000 /s:rom_code_file). After I modified the jumper setting to boot from DOC, nothing happened.

Thanks.

Regards,
David

nobody wrote on Tuesday, March 28, 2006:

Unless you are doing something clever with Open Watcom and making the code romable (I think this is possible with OW), then the exe you get should be booted from DOS.

Can you load DOS on your piloflash board and boot FreeRTOS from that as per the flashlite 186 demo?  You can use FreeDOS, or the DOS supplied by JK micro.

nobody wrote on Tuesday, March 28, 2006:

I don’t get it. Why do we need to boot FreeRTOS from DOS? Is FreeRTOS a program run under DOS? Can we boot FreeRTOS directly without any part of DOS? Thanks.

Regards,
David

nobody wrote on Tuesday, March 28, 2006:

You don’t have to boot FreeRTOS from DOS.  On most platforms this would never be done.  But if you are using Open Watcom then you are probably building a dos executable.

The Flashlite 186 is an x86 based board that comes with dos preinstalled.  Hence, building a dos executable is a convenient was of booting FreeRTOS on that platform.

You said you were using a converter program to convert your .exe.  If you are building a .exe then you are not building a romable image.

nobody wrote on Tuesday, March 28, 2006:

Now I get it. Booting FreeRTOS could be running FreeRTOS under DOS and then replacing the DOS to exclusively control the hardware. Thanks.

However, I’d still like to know some hints to booting FreeRTOS from Disk-On-Chip without DOS. And the following flow is what I think.

Reset --> picoBIOS --> TrueFFS BIOS --> boot loader(necessary?) --> FreeRTOS

Please correct me if I am wrong. Thanks.

Regards,
David