NetBSD/mipsco: Frequently Asked Questions

NVRAM Setup procedure

If you are having problems with BOOTP and see that your ethernet address is 00:00:00:00:00:00, then the most likely cause is your NVRAM has reached the end of its battery life.

The only way to solve the problem is to replace the MK48T02 NVRAM chip which is located near U-C8H1 on the main board. You will have to remove the Power Supply and look for a chip of non-standard height.

Unfortunately the MIPS designer engineers decided to make the first 1k of the NVRAM read only. The only way you can reprogram your Ethernet MAC address is to use another machine. The important values are at the start of memory and should be setup as follows:


Address Contents
0x0 MSB of MAC address
0x1 ..
0x2 ..
0x3 ..
0x4 ..
0x5 LSB of MAC address
0x6 Machine type (0x0a = Mips Magnum 3000)
0x7 ???
0x8 ???
0x9 ASCII Serial Number - 1st digit
0xa ASCII Serial Number
0xb ASCII Serial Number
0xc ASCII Serial Number - last digit

Additional information about the MK48T02 NVRAM chip can be found in the Sun NVRAM/Hostid FAQ.

The procedure for using a Sun IPX, SS1 or SS2 for reprogramming the NVRAM is as follows:

  1. Remove NVRAM from Mips machine and install into Sun Workstation

  2. Boot Sun Workstation and break into firmware monitor

  3. Enter new command mode by entering n

  4. Read the machine serial number which should look like 00ABCD-9111 where ABCD is a 4 digit serial number.

  5. Type the following commands in sequence:

        02000000 obio 0 map-page
        0 7f8 ff fill
        0 0 c!
        0 1 c!
        6b 2 c!
        AB 3 c!        (AB is first 2 digits of serial number)
        52 4 c!
        CD 5 c!        (CD is last 2 digits of serial number)
        0a 6 c!
        10 7 c!
        44 8 c!
        3A 9 c!        (3 followed by first serial number digit)
        3B a c!        (3 followed by second serial number digit)
        3C b c!        (3 followed by third serial number digit)
        3D c c!        (3 followed by last serial number digit)
  6. While at the monitor prompt immediately power down the machine (don't attempt to reboot otherwise the NVRAM will be reinitialized). Transplant the MK48T02 chip into your Mips machine.

  7. With a newly initialized NVRAM chip you will hear a beep at powerup and see the startup diagnostics when you connect a terminal to serial 1 at 9600 baud.

    You will probably witness a NVRAM checksum error - at this stage we are unable to locate enough information about the NVRAM format and checksum procedure to correct this. For now the machine will be usable on the network even with a checksum failure.