C-21
REGISTERS
PSW1
Address:
S:D1H
Reset State:
0000 0000B
Program Status Word 1. PSW1 contains bits that reflect the results of operations and bits that select
the register bank for registers R0–R7.
7
0
CY
AC
N
RS1
RS0
OV
Z
—
Bit
Number
Bit
Mnemonic
Function
7
CY
Carry Flag:
Identical to the CY bit in the PSW register.
6
AC
Auxiliary Carry Flag:
Identical to the AC bit in the PSW register.
5
N
Negative Flag:
This bit is set if the result of the last logical or arithmetic operation was
negative. Otherwise it is cleared.
4:3
RS1:0
Register Bank Select Bits 0 and 1:
Identical to the RS1:0 bits in the PSW register.
2
OV
Overflow Flag:
Identical to the OV bit in the PSW register.
1
Z
Zero Flag:
This flag is set if the result of the last logical or arithmetic operation is
zero. Otherwise it is cleared.
0
—
Reserved:
The value read from this bit is indeterminate. Write a zero to this bit.
RCAP2H, RCAP2L
Address: RCAP2H S:CBH
RCAP2L S:CAH
Reset State: 0000 0000B
Timer 2 Reload/Capture Registers. This register pair stores 16-bit values to be loaded into or captured
from the timer register (TH2/TL2) in timer 2.
7
0
High/Low Byte of Timer 2 Reload/Capture Value
Bit
Number
Bit
Mnemonic
Function
7:0
RCAP2H.7:0
RCAP2L.7:0
High byte of the timer 2 reload/recapture register
Low byte of the timer 2 reload/recapture register
Summary of Contents for 8XC251SA
Page 2: ......
Page 3: ...May 1996 8XC251SA 8XC251SB 8XC251SP 8XC251SQ Embedded Microcontroller User s Manual...
Page 18: ......
Page 19: ...1 Guide to This Manual...
Page 20: ......
Page 30: ......
Page 31: ...2 Architectural Overview...
Page 32: ......
Page 41: ...3 Address Spaces...
Page 42: ......
Page 63: ...4 Device Configuration...
Page 64: ......
Page 81: ...5 Programming...
Page 82: ......
Page 102: ......
Page 103: ...6 Interrupt System...
Page 104: ......
Page 120: ......
Page 121: ...7 Input Output Ports...
Page 122: ......
Page 132: ......
Page 133: ...8 Timer Counters and Watchdog Timer...
Page 134: ......
Page 153: ...9 Programmable Counter Array...
Page 154: ......
Page 170: ......
Page 171: ...10 Serial I O Port...
Page 172: ......
Page 187: ...11 Minimum Hardware Setup...
Page 188: ......
Page 197: ...12 Special Operating Modes...
Page 198: ......
Page 206: ......
Page 207: ...13 External Memory Interface...
Page 208: ......
Page 239: ...14 Programming and Verifying Nonvolatile Memory...
Page 240: ......
Page 250: ......
Page 251: ...A Instruction Set Reference...
Page 252: ......
Page 390: ......
Page 391: ...B Signal Descriptions...
Page 392: ......
Page 400: ......
Page 401: ...C Registers...
Page 402: ......
Page 436: ......
Page 437: ...Glossary...
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Page 446: ......
Page 447: ...Index...
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