pc87591l National Semiconductor Corporation, pc87591l Datasheet - Page 212

• Manufacturer Part Number: pc87591l
• Description: Lpc Mobile Embedded Controllers
• Manufacturer: National Semiconductor Corporation

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Embedded Controller Modules
Low-Power Threshold Comparison Mode (ACMMOD = 11
1. Set the desired threshold value in bits THRSHD(5-0) in THRDAT register.
2. Start a new periodic, low-power threshold comparison by setting START in ACMCTS register to 1.
3. When there is an input under (or over) threshold event, software can detect the event by waiting for OVUNTHEV in
4. Read comparison result for inputs 0 to 7 by reading bits CMPIN(0-7) in CMPRES register.
5. Clear the event flag (release the ACM interrupt if enabled) by writing 1 to OVUNTHEV in ACMCTS register.
Polling Driven Operation. Valid measurement results may be retrieved by polling the event flags in ACMCTS register,
EOMEV, EOCEV or OVUNTHEV, according to the selected operation mode. After reading the relevant data, clear the polled
event flag by writing 1.
Interrupt Driven Operation. When receiving an active ACM interrupt request, the software should check the two event
flags, EOMEV or OVUNTHEV, to identify the source of the interrupt. After reading the relevant data, clear (by setting to 1)
the event flag that caused the interrupt. Clearing the flag releases the ACM interrupt request.
4.14.5 ACM Registers
The ACM control/status and data out register set interfaces with the core through the Peripheral bus.
For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.
ACM Register Map
The ACM register set contains four control and status registers and nine data out registers.
ACMCTS register to be set to 1.
ACMCTS
ACMCNF
ACMTIM
THRDAT
CMPRES
VOLDAT0
VOLDAT1
VOLDAT2
VOLDAT3
VOLDAT4
VOLDAT5
VOLDAT6
VOLDAT7
Mnemonic
ACM Control and Status
ACM Configuration
ACM Timing Control
Comparison Threshold Data
Comparison Result
Reserved
Voltage Level Data - Input 0
Voltage Level Data - Input 1
Voltage Level Data - Input 2
Voltage Level Data - Input 3
Voltage Level Data - Input 4
Voltage Level Data - Input 5
Voltage Level Data - Input 6
Voltage Level Data - Input 7
(Continued)
Table 27. ACM Register Map
Register Name
212
2
)
Varies per bit
Type
R/W
R/W
R/W
RO
RO
RO
RO
RO
RO
RO
RO
RO
Revision 1.07