From 5a7bc73aed2e8a7e3feab901b96236d00574e68b Mon Sep 17 00:00:00 2001 From: "Eric J. Bowersox" Date: Wed, 29 May 2013 22:25:41 -0600 Subject: [PATCH] added README file preparatory to push to GitHub --- README | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+) create mode 100644 README diff --git a/README b/README new file mode 100644 index 0000000..68d8faa --- /dev/null +++ b/README @@ -0,0 +1,63 @@ +The COMROGUE Operating System for Raspberry Pi + +Copyright (c) 2013, Eric J. Bowersox / Erbosoft Enterprises +All rights reserved. +See the file "COPYRIGHT" for full copyright information. +------------------------------------------------------------------------------- +BACKGROUND + +The COMROGUE operating system stems from some ideas I had back when I was primarily a Windows developer working +with COM (in the late 1990's or so). The COM concept of interfaces seemed so elegant, I wondered if it would be +possible to do an entire operating system with a COM paradigm, that is, where every "system call" was actually a +call to a COM interface. Some interfaces might be ones defined by the existing COM implementation (for instance, +"file handles" would be IStream pointers, and memory might be allocated from the heap via an IMalloc interface), +others would be entirely novel. For one reason and another, I never did much with this, though I toyed with the +idea at one point using VirtualBox on an x86 system. The Raspberry Pi, however, offers a unique possibility, in +that its generic hardware is much more limited in scope than a PC's, so something ike this might just be possible +without too much fiddling with differences in hardware. + +Needless to say, this will be considered a "work in progress" for quite some time to come. :-) + +BUILDING + +You will need a cross-compiler setup on Linux; I use gcc-4.7.1 and binutils-2.22, installed in the tree +/opt/gnuarm and with the prefix "arm-none-eabi". Other versions MAY work. The compiler tools are located +with the variables ARMDIR and ARMPREFIX in the armcompile.mk file. + +To build the "pidl" MIDL compiler (in tools/pidl), you will need Perl and Yapp installed. + +You will also need GNU Make to execute everything (of course). + +The command "make" in the root directory of the source will build everything. The COMROGUE kernel will be in +kernel/kernel.img when the build is finished. + +EXECUTING + +Use a blank, FAT-formatted SD card (almost any size will do; I use 2 Gb cards as they're fairly common and cheap +these days). Download the current Raspberry Pi firmware files from https://github.com/raspberrypi/firmware; the +files you need will be bootcode.bin, fixup.dat, and start.elf in the boot/ subdirectory. Copy those three files +to your SD card, along with the kernel.img file from COMROGUE's kernel/ directory. Insert the card into your +Raspberry Pi and power up. + +Right now, the only output you'll see comes via the "mini-UART" serial output, which COMROGUE uses for trace output. +To see it, you'll need a couple of parts sold by Spark Fun Electronics of Boulder, CO: + +* FTDI Basic Breakout (3.3V), https://www.sparkfun.com/products/9873 +* Jumper Wires Premium 6" M/F (10-pack), https://www.sparkfun.com/products/9140 + +You'll also need a USB A-to-mini-B cable to hook the serial converter board to your PC's USB port. + +Connect jumper wires between the pins of the FTDI board and the GPIO connector on the Raspberry Pi as follows: + +* GPIO pin 6 -> GND (ground) on FTDI. (Suggested jumper wire color: black.) +* GPIO pin 8 -> RXI (receive input) on FTDI. (Suggested jumper wire color: red, for data *R*eceived from the Pi.) +* GPIO pin 10 -> TXO (transmit output) on FTDI. (Suggested jumper wire color: green, for data *G*oing to the Pi.) + +Connect the FTDI to your computer with the USB A-to-mini-B cable. On your PC, open Minicom and connect to port +/dev/ttyUSB0. Set the program to 115200 baud, 8 data bits, no parity, 1 stop bit, NO flow control (either hardware +or software). You should see some messages from COMROGUE when you apply power to the Pi. + +FURTHER INFORMATION + +The documentation/ directory will eventually contain more documentation on how the system works/will work. In +the meantime, I have tried to comment the code well enough to show what's going on.