MC68HC908GT16_07 Datasheet, PDF (281/292 Pages) Freescale Semiconductor, Inc – Microcontrollers

Appendix A
MC68HC08GT16
A.1 Introduction
This section introduces the MC68HC08GT16, the ROM part equivalent to the MC68HC908GT16. The
entire data book apply to this ROM device, with exceptions outlined in this appendix.
Table A-1. Summary of MC68HC08GT16 and MC68HC908GT16 Differences
Memory ($C000–$FDFF)
User vectors ($FFDC–$FFFF)
Registers at $FE08 and $FF7E
Registers at $FF80 and $FF81
Monitor ROM
MC68HC08GT16
15,872 bytes ROM
36 bytes ROM
Not used;
Locations are reserved.
ICG trim registers with fixed values.
Used for testing purposes only.
MC68HC908GT16
15,872 bytes Flash
36 bytes Flash
Flash related registers.
$FE08 — FLCR
$FF7E — FLBPR
ICG user trim registers.
Used for testing and Flash programming/erasing.
A.2 MCU Block Diagram
Figure A-1 shows the block diagram of the MC68HC08GT16.
A.3 Memory Map
The MC68HC08GT16 has 15,872 bytes of user ROM from $C000 to $FDFF, and 36 bytes of user ROM
vectors from $FFDC to $FFFF. On the MC68HC908GT16, these memory locations are Flash memory.
Table A-2 shows the memory map of the MC68HC08GT16.
A.4 Reserved Registers
The two registers at $FE08 and $FF7E are reserved locations on the MC68HC08GT16.
On the MC68HC908GT16, these two locations are the Flash control register and the Flash block protect
register respectively.
MC68HC908GT16 • MC68HC908GT8 • MC68HC08GT16 Data Sheet, Rev. 5.0
Freescale Semiconductor
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