
Chapter 3
3.2.1 R3 (Status Flag Register)
The Status Flag Register contains important status information; including the
status of the ALU, processor-reset condition, and program page select bits.
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
PS2 PS1 PS0 T
P
Z DC C
Bit
Description
Bit 0 (C)
Carry bit
Bit 1 (DC)
Auxiliary carry flag. Set to “1” while a carry is performed from low
nibble to high nibble
Bit 2 (Z)
Zero flag. Set to “1” if the result of an arithmetic or logic operation is
zero
Bit 3 (P)
Power down bit. Set to “1” during power-on reset or with a “WDTC”
command. Reset to “0” with the “SLEP” command
Bit 4 (T)
Set to “1” with the “SLEP” and “WDTC” command, or during power
on reset. Reset to “0” with WDT time-out
Bit 5 (PS0)
~
7 (PS2)
Page select bit. PS0
~
PS2 are loaded into the 11th to 13th bits of
the program counter, selecting one of the available program
memory pages. The value is set with the “PAGE” instruction
3.2.2 R4 (RAM Select Register)
Bits 5~0 of RAM Select Register are used for indirect address ranging from
0x00~0x3F. Bits 7 and 6 are used for data RAM bank selection. You can use
“BANK n” instruction for RAM bank switch. Refer to Section 2.4.1,
Data
Memory
for more detailed description on this topic.
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bank Select Bits
Indirect Address for R0 (0x00~0x3F)
Bits 7 & 5 Selected Data RAM Bank
000 Bank
0
001 Bank
1
010 Bank
2
011 Bank
3
18
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System Control
EM60000Series User’s Manual
Содержание EM60000 series
Страница 8: ...Contents viii Contents EM60000 Series User s Manual ...
Страница 24: ...Chapter 2 16 Architecture EM60000 Series User s Manual ...
Страница 54: ...Chapter 4 46 Special Function Control EM60000Series User s Manual ...
Страница 80: ...Chapter 5 72 Instruction Set EM60000Series User s Manual ...