If you're using custom hardware, you'll need a ROM monitor to
help bring it up. A monitor generally provides a simple command
prompt, with options for reading/writing memory and perhaps some
power-on testing facilities which are useful before the kernel boots.
ROM monitors invariably include bootloader
but if your device goes into production you may want a standalone
boot loader or a stripped-down ROM monitor. There are several available
on the net:
This is an actively developed ROM monitor and Linux boot loader
ideal for custom boards, derived from 8xxROM and FADSROM. It includes
support for BOOTP
, RARP and TFTP
image downloading and booting.
The Linux Monitor (LiMon?
) is a low level system start utility for
the SBC8260. It also includes BOOTP
The PMON/2000 BootROM?
Monitor (PMON/2000) permits full-featured
debugging to be performed on a target board that has a serial port,
512KB of ROM, and 128KB of RAM that can be dedicated to the Prom
It is currently targeted for the IBM 403, 8xx is a goal for the
future. It is ROM-able so you can boot directly from it, and has
some ifdef's to slim the code down to as little as 10K or as large
as 30K. It accepts S records over the serial port for loading other
software. Unfortunately it is written in assembly, but then it's
really small and is released under the GPL
. It is a small
implementation of FORTH which is handy for testing and small programs,
although the author went overboard and included multitasking and a
lot of low-level device control words.
DINK32 was developed as an internal Motorola PowerPC
tool to help
debug silicon as well as code. It runs on a variety of boards including
the Yellowknife, Sandpoint, Excimer and Maximer. DINK32 has the full
complement of commands. DINK32 supports all of the currently available
microprocessors including the 603, 603e, 604 family, the integrated
processor, 8200 the 8240, the 7xx family and the 7400. DINK32 is a great
source for example code when initializing the MPC105, MPC106, MPC107 memory
controllers/bridge chips. DINK32 source code also includes sample code for
the MPC8240 subsystems, DMA
, EPIC, I2C, and I2O.
Derived from FADSROM. No longer actively developed, and only really of
historical interest as it has been superseded by ppcboot
An old ROM monitor and loader written for the FADS
FADSROM has been superseded by ppcboot