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MDT2005
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P. 3
VER1.1
6. Memory Map
(A) Register Map
Address
Description
00
Indirect Addressing Register
01
RTCC
02
PC
03
STATUS
04
MSR
05
Port A
06
Port B
07~1F
Internal RAM, General Purpose Register
(1) IAR ( Indirect Address Register) : R0
(2) RTCC (Real Time Counter/Counter Register) : R1
(3) PC (Program Counter) : R2
Write PC, CALL --- always 0
LJUMP, JUMP, LCALL --- from instruction word
RTIW, RET --- from STACK
A9
A8
A7~A0
Write PC, JUMP, CALL --- always 0 (ROM 0.5K)
LJUMP, LCALL --- from instruction word
RTIW, RET --- from STACK
Write PC --- from ALU
LJUMP, JUMP, LCALL, CALL --- from instruction word
RTIW, RET --- from STACK