OVERVIEW | TECHNICAL | SF.NET PROJECT PAGE | BROWSE CVS Description This project develops the code in the C-ONE's boot ROM. The boot ROM is responsible for configuring the main FPGA and loading any ROM images that it needs to start. It can also preload applications into system RAM, and an animated power on logo is included as an example of this. Finally, it can load a program into its own environment and execute it after it's done booting the main system. Architecture The C-ONE motherboard has two FPGAs. The smaller one, an Altera ACEX EP1K30, is configured from the on board Flash ROM at power up. The larger FGPA, an ACEX EP1K100, needs to be configured before the computer can start. In order to be as flexible as possible, the smaller FPGA hosts a boot environment that loads the configuration files from disk. This allows you to easily swap between several different configurations. It also means that upgrading the C-ONE with new hardware configurations is as simple as putting new boot files on a floppy or your hard drive. The 1K30 contains a clone of an Amstrad CPC, with a RISC CPU that is capable of emulating both a Z80 and a 6502. It can address 1 MB of RAM from the Multimedia SIMM. The CPC core has access to all the I/O devices it needs to boot the system. You can also quit the boot process, get a basic prompt, and use it as a CPC computer. The C1 can program the on board Flash ROM in system. This means that every aspect of the C1 is user upgradeable, except for the CPLDs (these require a JTAG interface and cable). Boot Procedure The code starts with the first controller and selects the first device. It then tries to find the boot files in the first partition on that device. If it can't find the boot files, it proceeds to the next device. If there are no more devices on that controller, it proceeds to the next controller, until there are no more controllers. The following boot devices are supported: Controller Device Filesystems Status Floppy 1.44 MB 3.5" HD drive FAT12 not implemented IDE Hard Disk/Compact Flash FAT12, FAT16, FAT32 working IDE CD-ROM ISO9660 working ROM Flash ROM Custom ROMFS working

News Tobias Gubener's code changes merged with CVS, docs updated     magervalp - 2004-09-29 05:49   -   C-ONE boot code The code changes Tobias Gubener needed to do to get the boot code to run on his CPC core have been merged with the CVS tree. The tech docs on the c1boot site have been updated to reflect the changes. [Read More/Comment] Tech details on flash programming posted     magervalp - 2003-08-18 09:31   -   C-ONE boot code The C-ONE boot homepage has been updated with a detailed I/O memory map, and information on how to write to the flash rom: http://c1boot.sourceforge.net/c1flash.shtml [Read More/Comment] Keyboard and volume name code fixed     magervalp - 2003-06-18 06:08   -   C-ONE boot code The hw bug in the keyboard FIFO was fixed, so the boot menu works correctly now. A small bug relating to FAT volume names was fixed - the code would end up in an endless loop if the volume name entry had the Archived attribute bit set. [Read More/Comment] [News archive]

In order to boot successfully, the configuration files need to adhere to these rules:

• The configuration files should be in a dir in the root called "BOOT".
• There can be a total of 10 configs, prefixed 0 to 9.
• Each config should as a bare minium have a file named "xFPGA.BIN" where x is the config number. This file is sent to the 1K100 as FPGA configuration data. This file can also be RLE compressed, and is then named "xFPGA.RLE".
• Each config may also have up to 16 memory images named "xRaaaaaa.BIN" where x is the config number and aaaaaa is the 24-bit address in hex where the image should be loaded.
• Each config may also have a file called "xDRIVE.BIN" (where x is the config number) that is loaded and executed by the drive CPU after the main FPGA has been successfully configured.
• Each config may also have a file called "xDESC.TXT" (where x is the config number) which should be a plain ascii file with CR/LF linebreaks that should contain a one line description of the configuration, with max 32 characters. the other lines are optional and should have max 39 characters per line. Only ascii characters 32-126 are allowed.

It should be noted that on FAT and ISO9660 drives, only the 8.3 filename is used. VFAT, Joliet, and other extensions are silently ignored.

As an example, this is what the C64 mode configuration files could be called if they were on an MS-DOS drive mounted as D:

D:\BOOT\0DESC.TXT           ; description for boot menu
D:\BOOT\0DRIVE.BIN          ; executed in the drive cpu after booting
D:\BOOT\0FPGA.RLE           ; RLE compressed FPGA core
D:\BOOT\0R000000.BIN        ; the main FPGA core is loaded as a rom
D:\BOOT\0R051000.BIN        ; char rom at $1000
D:\BOOT\0R059000.BIN        ; char rom at $9000
D:\BOOT\0R05A000.BIN        ; basic rom
D:\BOOT\0R05D000.BIN        ; char rom at $d000
D:\BOOT\0R05E000.BIN        ; kernal rom

After the FPGA has been configured and the memory images loaded, one of two things happen. If an xDRIVE.BIN file was found, it's loaded and executed. If no such file was found, the /DMA line of the 65816 is set high (allowing it to start), and the drive CPU sits in an endless loop.

Known Bugs

In the current version of the boot rom, the following doesn't work as advertised:

• The floppy code has not been implemented yet.

Developers

• Per Olofsson (MagerValp@cling.gu.se) is the main boot rom developer and project maintainer of this project.
• Adrian Gonzalez (adrianglz@globalpc.net) added FAT12, and is doing a user friendly flash utility.
• Jeri Ellsworth (cm_easy@yahoo.com) developed the hardware.
• Tobias Gubener (t.gubener@gmx.de) is working on the CPC core.

License

Copyright © 2003-2004, the C-ONE Boot Project
All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

• Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
• Neither the name of the C-ONE Boot Project nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Links

http://c64upgra.de/c-one/

The official home page of the C-ONE

http://groups.yahoo.com/group/CommodoreOne/

The C-ONE mailing list

http://www.cling.gu.se/~cl3polof/c1/

Pictures of my development board