MC68HC05L28 Datasheet, PDF (37/156 Pages) Motorola, Inc – Flexible general-purpose microcomputer

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MEMORY AND REGISTERS
The MC68HC05L28 has a 16K byte memory map consisting of registers, user ROM, user RAM,
bootstrap ROM, LCD RAM, EEPROM and I/O, as shown in Figure 3-1.
3.1
Registers
All the I/O, control and status registers of the MC68HC05L28 are contained within the first 64-byte
block of the memory map (address $0000 to $003F).
3.2
LCD RAM
The 12 bytes of LCD RAM are located at address $0040 to $004B. This RAM is used to store the
data needed for the LCD. See Section 7.1 for further details of the organization of these bits.
3.3
RAM
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.
MC68HC05L28
MEMORY AND REGISTERS
TPG
MOTOROLA
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