Motorola PowerPC MBX

Overview

RedBoot uses the SMC1/COM1 serial port. The default serial port settings are 38400,8,N,1. Ethernet is also supported using the 10-base T connector.

Management of onboard flash is also supported. Two basic RedBoot configurations are supported:

Initial Installation Method

Device programmer is used to program the XU1 socketed flash part (AM29F040B) with the ROM version of RedBoot. - Use the on-board EPPC-Bug monitor to update RedBoot.

This assumes that you have EPPC-Bug in the on-board flash. This can be determined by setting up the board according to the following instructions and powering up the board.

The EPPC-Bug prompt should appear on the SMC1 connector at 9600 baud, 8N1.

  1. Set jumper 3 to 2-3 [allow XU1 flash to be programmed]

  2. Set jumper 4 to 2-3 [boot EPPC-Bug]

If it is available, program the flash by following these steps:

  1. Prepare EPPC-Bug for download:
    EPPC-Bug>lo 0
    At this point the monitor is ready for input. It will not return the prompt until the file has been downloaded.

  2. Use the terminal emulator's ASCII download feature (or a simple clipboard copy/paste operation) to download the redboot.ppcbug file.

    Note that on Linux, Minicom's ASCII download feature seems to be broken. A workaround is to load the file into emacs (or another editor) and copy the full contents to the clipboard. Then press the mouse paste-button (usually the middle one) over the Minicom window.

  3. Program the flash with the downloaded data:
    EPPC-Bug>pflash 40000 60000 fc000000

  4. Switch off the power, and change jumper 4 to 1-2. Turn on the power again. The board should now boot using the newly programmed RedBoot.

To install RedBoot on a target that already has eCos GDB stubs, download the RAM version of RedBoot and run it. Initialize the flash image directory:
RedBoot> fi init
Then download the ROM version of RedBoot and program it into flash:
RedBoot> load redboot_ROM.srec -b 0x80100000
RedBoot> fi cr RedBoot -f 0xFE000000 -b 0x00040000 -l 0x20000

Flash management

Special RedBoot Commands

None.

Memory Maps

Memory Maps RedBoot sets up the following memory map on the MBX board.
Physical Address Range Description
----------------------- -----------
0x00000000 - 0x003fffff DRAM
0xfa100000 - 0xfa100003 LEDs
0xfe000000 - 0xfe07ffff flash (AMD29F040B)
0xff000000 - 0xff0fffff MPC registers

Resource Usage

The flash based RedBoot image occupies flash addresses 0xfe000000 - 0xfe01ffff. RedBoot also reserves RAM (0x00000000 - 0x0001ffff) for RedBoot runtime uses. RAM based RedBoot configurations are designed to run from RAM at physical addresses 0x00020000 - 0x0004ffff. RAM physical addresses from 0x00050000 to the end of RAM are available for general use, such as a temporary scratchpad for downloaded images, before they are written to flash.

Rebuilding RedBoot

The instructions in Chapter 3 should be followed. The values for TARGET, ARCH_DIR and PLATFORM_DIR on this platform are “mbx”, “powerpc” and “mbx” respectively. Note that the configuration export files supplied in the hal/powerpc/mbx/VERSION/misc directory in the RedBoot source tree should be used.