Motorola Single Board Computer, MVME5100 manual Hardware and Firmware Initialization

3

PPCBug Firmware

For example, if a breakpoint has been specified, then control returns to the debugger when the breakpoint is encountered during execution of the user program. Alternately, the user program could return to the debugger by means of the System Call Handler routine RETURN (described in the PPCBug Firmware Package User’s Manual). For more about this, refer to the GD, GO, and GT command descriptions in the PPCBug Firmware Package User’s Manual, listed in Appendix C, Related Documentation .

A debugger command is made up of the following parts:

❏The command name, either uppercase or lowercase (for example, MD or md)

❏Any required arguments, as specified by command

❏At least one space before the first argument. Precede all other arguments with either a space or comma.

❏One or more options. Precede an option or a string of options with a semicolon (;). If no option is entered, the command’s default option conditions are used.

Hardware and Firmware Initialization

The debugger performs the hardware and firmware initialization process. This process occurs each time the MVME5100 is reset or powered up. The steps listed below are a high-level outline; be aware that not all of the detailed steps are listed.

1.Sets MPU.MSR to known value.

2.Invalidates the MPU's data/instruction caches.

3.Clears all segment registers of the MPU.

4.Clears all block address translation registers of the MPU.

5.Initializes the MPU-bus-to-PCI-bus bridge device.

6.Initializes the PCI-bus-to-ISA-bus bridge device.

7.Calculates the external bus clock speed of the MPU.

3-4 Computer Group Literature Center Web Site