MC68HC05J3 Datasheet, PDF (25/92 Pages) Motorola, Inc – High-density Complementary Metal Oxide Semiconductor (HCMOS) Microcomputer Unit

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MEMORY AND REGISTERS
The MC68HC05J3 has a 4 kbyte memory map consisting of registers (for I/O, control and status),
User RAM, User ROM, bootloader ROM and reset and interrupt vectors as shown in Figure 3-1.
3.1
Registers
All the I/O, control and status registers of the MC68HC05J3 are contained within the first 32-byte
block of the memory map, as detailed in Table 3-1.
3.2
RAM
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 may extend 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.
3.3
Non-volatile memory (NVM)
The NVM consists of 2048 bytes of ROM (MC68HC05J3) from $0700 to $0EFF, 240 bytes of
bootloader ROM and 16 bytes of user vectors ($0FF0 to $0FFF).
MC68HC05J3
MEMORY AND REGISTERS
TPG
MOTOROLA
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