double is an alias for float. IOW, only 32-bit single precision floats are supported. This isn't conformant, but OK for some embedded systems (e.g. RetroBSD) and simple compilers like this. Also, the following operators are not supported with floats at the moment: ++, --, +=, -=, *=, /=. But +, -, *, /, =, ||, &&, ?:, !, comparison, casts, if/while/for are OK.
This is the RetroBSD source directory.
Source Roadmap
bin User commands.
etc Template files for /etc.
include System include files.
lib System libraries.
libexec System binaries.
sbin System administration commands.
share Shared resources.
sys Kernel sources.
tools Build tools and simulators.
Supported hardware
- Fubarino SD board.
- Olimex Duinomite, Duinomite-Mini, Duinomite-Mega and Duinomite-eMega boards.
- Olimex Pinguino-Micro board with PIC32MX795F512H microcontroller.
- Maximite and Colour Maximite computers.
- Majenko SDXL board.
- 4D Systems Picadillo-35T board.
- MikroElektronika MultiMedia Board for PIC32MX7.
- chipKIT Max32 board with SD card shield.
- chipKIT WF32 board with 2.4" LCD TFT display shield.
- Sparkfun UBW32 board with SD card slot.
- Microchip Explorer 16 board, with PIC32 CAN-USB plug-in module and SD & MMC pictail.
- Microchip PIC32 USB or Ethernet Starter Kit, with I/O Expansion board and SD & MMC pictail.
Build
To compile everything from sources, you'll need some packages installed, namely: Berkeley YACC, GNU bison, flex, groff, ELF library and FUSE library. Under Ubuntu, for example, you can do it by command:
$ sudo apt-get install bison byacc flex groff-base libelf-dev libfuse-dev
You can change a desired filesystem size and swap area size, as required. Default is:
FS_MBYTES = 100
SWAP_MBYTES = 2
To compile the kernel and build a filesystem image, run:
$ make
A resulting root filesystem image is in file sdcard.img.
A kernel is in file unix.hex in your target board subdirectory.
Filesystem image
You need to put a filesystem image on a SD card. On Windows, use Win32DiskImager utility (https://launchpad.net/win32-image-writer/+download). On Linux, run:
$ sudo dd if=sdcard.img of=/dev/XYZ
Here XYZ is a device name of SD card, as recognized by Linux (sdb in my case).
Install kernel
Kernel image should be written to PIC32 flash memory. The procedure depends on a board used.
Max32 board:
Use a pic32prog utility (http://code.google.com/p/pic32prog/) and a USB cable to install a kernel:
$ pic32prog -d /dev/ttyUSB0 sys/pic32/max32/unix.hex
Here you need to change AVRTOOLS path and tty name according to your system.
UBW32 board:
Use a pic32prog utility (http://code.google.com/p/pic32prog/) and a USB cable to install a kernel:
$ pic32prog sys/pic32/ubw32/unix.hex
Maximite:
Use the bootload program for Windows, available for download by link: http://geoffg.net/Downloads/Maximite/Maximite_Update_V2.7B.zip
Explorer 16 board:
There is an auxiliary PIC18 chip on the Explorer 16 board, which can be used as a built-in programmer device. You will need a PICkit 2 adapter to install a needed firmware, as described in article: http://www.paintyourdragon.com/?p=51 (section "Hack #2: Lose the PICkit 2, Save $35"). This should be done only once.
Then, you can use a pic32prog utility (http://code.google.com/p/pic32prog/) and a USB cable to install a kernel:
$ pic32prog sys/pic32/explorer16/unix.hex
PIC32 Starter Kit:
Use PICkit 2 adapter and software to install a boot loader from
file sys/pic32/starter-kit/boot.hex. This should be done only once.
Then, you can use a pic32prog utility (http://code.google.com/p/pic32prog/) and a USB cable to install a kernel:
$ pic32prog sys/pic32/starter-kit/unix.hex
Simulator
You can use a MIPS32 simulator to develop a debug a RetroBSD software, without a need for hardware board. By default, a simulator is configured to imitate a Max32 board. To build it:
$ cd tools/virtualmips
$ make
Run it:
$ ./pic32
Configuration of simulated board is stored in file pic32_max32.conf.