Motorola M68EVB912B32, User Manual

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OPERATION
68EVB912B32UM/D 3-56
3.9.1 On-Chip RAM
D-Bug12 requires 512 bytes of on-chip RAM for stack and variable storage. This usage is shown
in Table 3-5.
3.9.2 On-Chip EEPROM
D-Bug12 occupies Flash EEPROM starting at address $8000, as shown in Table 3-5. This area
is thus not available for emulation of a target application.
3.9.3 SCI Port Usage
D-Bug12 requires the MCU’s Serial Communications Interface (SCI) port for the terminal
interface. The SCI port is either connected (default) or disconnected from the RS-232C RXD
and TXD signals by means of jumpers W1 and W2.
3.9.4 Dedicated MCU Pins
As used on the EVB with D-Bug12, the following MCU lines perform specific functions. If an
application requires their use, the EVB hardware and/or operating software must be custom-
configured, or special precautions must be taken in the application code to avoid conflicts with
the D-Bug12 usage.
PAD0 — EVB mode select pin (W3)
PAD1 — EVB mode select pin (W4)
PE5/MODA, and PE6/MODB — Sets MCU chip mode, normally single chip.