MC68HC05BD3 Datasheet, PDF (27/112 Pages) Motorola, Inc – HCMOS microcontroller

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MEMORY AND REGISTERS
The MC68HC05BD3/MC68HC705BD3/MC68HC05BD5 has a 16K-byte memory map consisting
of registers, user ROM/EPROM, user RAM, self-check/bootstrap ROM, and I/O as shown in
Figure 3-1.
3.1
Registers
All the I/O, control and status registers of the MC68HC05BD3 are contained within the first 48-byte
block of the memory map (address $0000 to $002F).
3.2
RAM (MC68HC05BD3)
The user RAM consists of 128 bytes of memory, from $0080 to $00FF. This is shared with a 64
byte stack area. The stack begins at $00FF and counts down to $00C0.
3.3
RAM (MC68HC705BD3/MC68HC05BD5)
The user RAM consists of 256 bytes of memory, from $0080 to $017F. This is shared with a 64
byte stack area. The stack begins at $00FF and counts down to $00C0.
Note:
Using the stack area for data storage or temporary work locations requires care to
prevent the data from being overwritten due to stacking from an interrupt or subroutine
call.
MC68HC05BD3
MEMORY AND REGISTERS
TPG
MOTOROLA
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