Motorola MVME166IG/D2 - Manual (Page 53)

BOOTBUG
MVME166IG/D2 3-7
3
6. Power up the system. 166Bug executes some self-checks and displays the
debugger prompt "
166-Bug> " (if 166Bug is in Board Mode). However, if
the ENV command (Appendix A) has put 166Bug in System Mode, the
system performs a selftest and tries to autoboot. Refer to the ENV and
MENU
commands. They are listed in Table 4-3.
If the confidence test fails, the test is aborted when the first fault is
encountered. If possible, an appropriate message is displayed, and control
then returns to the menu.
BOOTBUG
166BBug Implementation
The MVME166 board has a byte-wide EPROM in addition to the Flash
memory used to contain the debugger and diagnostics firmware. The EPROM
supplied contains the BootBug product (166BBug). Since Flash memory can be
electronically erased, the firmware contained in this EPROM is a miniature
version of the regular debugger product. It contains enough functionality to
enable downloading of object code (by means of the VMEbus, serial port, SCSI
bus, or the network) and reprogramming of the Flash memory.
The following table lists the the new commands available in the 166BBug
product.
Detailed descriptions of additional subset commands can be found in the
Debugging Package for Motorola 68K CISC CPUs User’s Manual.
There is a jumper on the MVME166 board that controls the operation of the
BootBug. If the jumper at J3 pins 7 and 8 is in place (GPI3), then the BootBug
(which always executes at reset and powerup) will unconditionally jump to
the debugger product contained in the Flash memory. If this jumper is
removed, execution will continue in the (diminished functionality) BootBug.
Before using some of the features of the MVME166 BootBug, some parameters
may need to be defined. For example, the SCSI ID, the Ethernet address, the
clock speed of the board, or possibly the mapping of VMEbus. There is a new
command provided for this purpose, the setup command. You should run
this command and answer the prompts to be sure the board is configured
properly before using any SCSI, VME, or Ethernet I/O.
Command Description
EXEC Execute User Program
SETUP Set "System" Parameters