mpc823rg Freescale Semiconductor, Inc, mpc823rg Datasheet - Page 282

• Manufacturer Part Number: mpc823rg
• Description: Mpc823 Powerquicc Integrated Communications Processor For Portable Systems
• Manufacturer: Freescale Semiconductor, Inc

12.5.1 Decrementer Register
The 32-bit decrementer (DEC) register is a special-purpose register defined by PowerPC
architecture. The decrementer causes an interrupt whenever Bit 0 changes from a logic 0 to
a logic 1. The contents of this register can be read or written to by the mfspr or mtspr
instruction. This register is undefined at reset. The decrementer is powered by standby
power and continues counting when standby power is applied. To enable the decrementer
control bits, use the timebase control and status register. The decrementer and timebase
share the same TMBCLK.
DEC—Decrementer
This field is used by a down counter to cause decrementer interrupts. A read of this register
always returns the current count value from the down counter.
DEC
NOTE: — = Undefined.
RESET
RESET
FIELD
FIELD
SPR
SPR
R/W
R/W
BIT
BIT
16
0
17
1
18
2
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For More Information On This Product,
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MPC823 REFERENCE MANUAL
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DEC
DEC
R/W
R/W
22
22
—
—
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System Interface Unit
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12-13
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