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The wiki is being retired!

Documentation is now handled by the same processes we use for code: Add something to the Documentation/ directory in the coreboot repo, and it will be rendered to Contributions welcome!

The RCA RM4100 was originally designed by Thomson Electronics and was called the IP1000. I was then manufactured by RCA and named the RM4100. It is a great little set-top-box for coreboot. Maintained by Joseph Smith.


Device/functionality Status Comments
CPU works OK Mobile Intel(R) Celeron(TM) CPU 733MHz
L1 cache enabled OK
L2 cache enabled OK 256 KB
L3 cache enabled N/A
Multiple CPU support N/A
Multi-core support N/A
Hardware virtualization N/A
SO-DIMM OK Onboard 128MB PC133
Dual channel support N/A
ECC support N/A
On-board Hardware
On-board IDE 3.5" OK Tested with hard drive.
On-board IDE 2.5" OK Tested with 2.5" hard drive and adapter.
On-board SATA N/A
On-board SCSI Unknown
On-board USB OK Tested with USB keyboard.
On-board VGA OK VGA support in coreboot works fine.
On-board Ethernet OK Onboard Intel 82562ET LAN On Motherboard (LOM) Design.
On-board Audio OK
On-board Modem OK
On-board FireWire N/A
On-board Smartcard reader N/A
On-board CompactFlash OK
On-board PCMCIA N/A
On-board Wifi N/A
On-board Bluetooth N/A
On-board SD card reader N/A
Add-on slots/cards
ISA add-on cards N/A
Audio/Modem-Riser (AMR/CNR) cards N/A
PCI add-on cards N/A
Mini-PCI add-on cards Unknown
Mini-PCI-Express add-on cards Unknown
PCI-X add-on cards Unknown
AGP graphics cards N/A
PCI Express x1 add-on cards N/A
PCI Express x2 add-on cards N/A
PCI Express x4 add-on cards N/A
PCI Express x8 add-on cards N/A
PCI Express x16 add-on cards N/A
PCI Express x32 add-on cards N/A
HTX add-on cards N/A
Legacy / Super I/O
Floppy N/A
Serial port 1 (COM1) OK
Serial port 2 (COM2) OK IR is connected to COM2.
Parallel port OK There is no actual Parallel connector, the Parallel is used to enable IR and control 3 LEDs.
PS/2 keyboard N/A
PS/2 mouse N/A
Game port N/A
Infrared OK
PC speaker N/A
DiskOnChip N/A
Trackpoint N/A
Touchpad N/A
Fn Hotkeys N/A
Fingerprint Reader N/A
Docking VGA N/A
Docking LAN N/A
Docking USB N/A
Docking Audio N/A
Docking Displayport N/A
Thinklight N/A
Webcam N/A
Sensors / fan control OK lm-sensors uses i801, smsc47m192.
Hardware watchdog Untested
SMBus Unknown
CAN bus N/A
CPU frequency scaling Untested
Other powersaving features WIP
Reboot WIP
Poweroff WIP
Suspend Unknown
Nonstandard LEDs OK Controlled by parallel port.
High precision event timers (HPET) N/A
Random number generator (RNG) N/A
Wake on modem ring Untested
Wake on LAN Untested Enabled on LOM Design, should work fine but untested.
Wake on keyboard Untested Supported by the Super I/O but not implemented.
Wake on mouse N/A
TPM Unknown
Flashrom WIP


RM4100 with PLCC Socket, IDE, & VGA Mods

  • Intel i830M4 Northbridge
  • Intel i82801DB ICH4 Southbridge
  • SMSC LPC47M192 SuperIO
  • 128MB PC133 SDRAM on board
  • Two USB 2.0 ports
  • 2 Ultra ATA/100/66/33 IDE channels (no connectors)
  • 64MB Compact Flash via IDE controller (upgradeable)
  • Integrated 10/100 Intel 82562ET LAN On Motherboard (LOM)
  • Integrated 2D and 3D graphics with AGP 4X interface
  • Conexant CX25873-13 High Performance Video Encoder
  • Optical SPDIF output (Dolby Digital)
  • Composite and S-Video outputs (Can deliver either NTSC or PAL video)
  • Integrated Conexant CX81801-94 SmartV.XX V.92, V.34, V.32 Data Modem
  • IR receiver for remote / keyboard

VGA vs. Headless

Before building coreboot for the RCA RM4100 there are a few settings to consider. Depending on whether you want VGA support or not, you might have to modify some files.

Headless (no VGA)

You have the ability to build a "headless" version of coreboot that will only output to the serial console:

Edit targets/rca/rm4100/ and change:

# option ROM_SIZE = 1024 * 1024
option ROM_SIZE = (1024 * 1024) - (64 * 1024)


option ROM_SIZE = 1024 * 1024
# option ROM_SIZE = (1024 * 1024) - (64 * 1024)

Also, change:



option CONFIG_PCI_ROM_RUN = 0 


option CONFIG_VIDEO_MB = 8


option CONFIG_VIDEO_MB = 0

Edit src/mainboard/rca/rm4100/ and comment out these lines so it looks like this:

#    chip drivers/pci/onboard		# Onboard VGA
     device pci 2.0 on end		# VGA (Intel 82830 CGC) 
#      register "rom_address" = "0xfff00000" 
#    end


If you do want VGA you can choose how much memory is pre-allocated for VGA. Possible options are:

## 0 for No memory pre-allocated (Graphics memory Disabled)
## 512 for DVMT (UMA) mode, 512K of memory pre-allocated for frame buffer
## 1 for DVMT (UMA) mode, 1M of memory pre-allocated for frame buffer
## 8 for DVMT (UMA) mode, 8M of memory pre-allocated for frame buffer

To adjust this edit targets/rca/rm4100/, edit the line


and change it to any of the options above. Note: Remember that if you do want VGA you will need the VGA BIOS file (vga.rom).


Next you will need to prepare a payload. For this tutorial I will use FILO to boot from a hard drive (Fedora Core 7). In the FILO directory run


like instructed in the INSTALL directions and then edit the file Config.


MENULST_FILE = "hda3:/boot/filo/menu.lst"

to (menu.lst is a symlink to grub.conf and FILO does not like that)

MENULST_FILE = "hda1:/grub/grub.conf"

to boot to GRUB on the Compact Flash card or

MENULST_FILE = "hdc1:/grub/grub.conf"

to boot from the harddrive (if you have the HD hack installed).


#SERIAL_SPEED = 115200



to insure we get output to the serial console. That should be it. Now you can run


again to build your payload ELF file. Once that finishes copy filo.elf to the /tmp directory, or you can adjust targets/rca/rm4100/ to point to where filo.elf is.

You can further reduce the size of filo.elf by disabling various unneeded options in FILO's Config file (e.g. support for filesystems you don't use).

Building coreboot

Now we are ready to build coreboot.

$ cd ~/coreboot-v2/targets
$ ./buildtarget rca/rm4100
$ cd rca/rm4100/rm4100
$ make

If you're using VGA you need to prepend your video BIOS to the coreboot.rom file. Copy your VGA BIOS file (vga.rom) to the ~/coreboot-v2/targets/rca/rm4100/rm4100 directory and then:

cat vga.rom coreboot.rom > bios.bin

Flashing coreboot

At last you're ready to flash bios.bin to your RM4100. If this is the first time, meaning your RM4100 still has the original BIOS, you need to use the method on the RM4100 Customizing website to flash, otherwise you can just use flashrom.

Public domain I, the copyright holder of this work, hereby release it into the public domain. This applies worldwide.

In case this is not legally possible:
I grant anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law.