The M68HC12A4 EVB is used to design, debug, and evaluate embedded systems based on the MC68HC812A4 device. By providing the essential MCU timing and I/O circuitry, the EVB simplifies user evaluation of prototype hardware and software.

• A prototype area that enables custom interfacing with the MCU's I/O and bus lines. These connections are broken out via on-board headers, which are immediately adjacent to the prototype area.
• Optionally, the ability to accommodate various types and configurations of external memory to suit a particular application's requirements.
• An EPROM-resident monitor program, DBug12, which is completely factory-configured and ready to use with an RS-232C-compatible terminal for writing and debugging user code.
• Two Serial Communications Interface (SCI) ports for environments in which the MCU's single-wire background debug mode (BDM) interface serves as the user interface. This mode requires a tool such as the SDI for background debugging, along with a host computer running the appropriate interface software.
  • Two methods for generating EVB user code:
  • For small programs or subroutines, DBug12 can be used to place object code directly into memory.
  • For larger programs, the Motorola MCUasm assembler (described on page 9) can be used on a host computer to generate S-Record object files that DBug12 then loads into memory.
  • The DBug12 monitor program is included with the 68HC812A4 EVB package. DBug12 is an EPROM-resident monitor program that enables writing, debugging, and programming of the MC68HC812A4's on-chip EEPROM through commands that directly alter memory.