mc68hc05l25 Freescale Semiconductor, Inc, mc68hc05l25 Datasheet - Page 25

• Manufacturer Part Number: mc68hc05l25
• Description: M68hc05 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

2.2.5 Reset Value
Values specified on the row marked Reset: are initial values of register bits after system reset. Those bits
unaffected by reset are marked with the letter U. Those bits that are unaffected by reset but initialized by
power-on reset are marked with an asterisk (*).
2.2.6 Option Map
Address locations $0000 through $000F are dual mapped. When the OPTM bit in the MISC register is
cleared, the main address map is accessed. When the OPTM bit in the MISC register is set, the option
address map is accessed.
2.2.7 Random-Access Memory (RAM)
The user RAM consists of 176 bytes (including the stack) at locations $0050 through $00FF. The stack
can access 64 locations beginning at address $00FF and proceeding down to $00C0.
2.3 Read-Only Memory (ROM)
This chip has a total of 6160 bytes of ROM. These are implemented as 6144 bytes of user ROM at
locations $0700 through $1EFF and 16 bytes of user vectors at locations $1FF0 through $1FFF. A total
of 240 bytes of test ROM and vectors is located from $1F00 through $1FEF.
Freescale Semiconductor
Although not necessary for this device, the OPTM bit should be cleared
when accessing memory locations $0010 and above for future
compatibility.
Using the stack area for data storage or temporary work locations requires
care to prevent it from being overwritten due to stacking from an interrupt
or subroutine call.
MC68HC05L25 Data Sheet, Rev. 3.1
NOTE
NOTE
Read-Only Memory (ROM)
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