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CHAPTER 16 8/10-BIT A/D CONVERTER
Table 16.4-1 Function Description of Each Bit of A/D Control Status Register 1 (ADCS1)
Bit name
Function
bit15
BUSY:
Busy bit
This bit indicates the operating status of the A/D converter
When this bit is "0", the A/D conversion has halted.
When this bit is "1", the A/D conversion is in progress.
When this bit is set to "0", the A/D conversion is forced to halt.
When this bit is set to "1", operation is not affected.
Note:
Do not set the forced A/D conversion stop and the activation (BUSY="0",
STRT="1") simultaneously.
bit14
INT:
Interrupt request
flag bit
This bit is a flag that requests an interrupt.
This bit is set to "1" when A/D conversion results are stored in the A/D data
register (ADCR0/ADCR1).
When this bit is set to "1" while the interrupt request enable bit (INTE) is "1", an
interrupt request is output.
When this bit is set to "0", the interrupt request is cleared.
When this bit is set to "1", operation is not affected.
When EI2OS is used, this bit is cleared to "0".
Note:
To clear the interrupt requests, stop the A/D conversion.
bit13
INTE:
Interrupt request
enable bit
This bit enables an interrupt request.
When the interrupt request flag bit (INT) is set to "1" while this bit is set to "1",
an interrupt request is output.
To use EI2OS, set this bit to "1".
bit12
PAUS:
Halt flag bit
This bit is set to "1" when the A/D conversion stops temporarily.
When EI2OS is used in continuous conversion mode, this bit is set to "1" if
transfer of the last piece of data to memory has not been completed even
though A/D conversion is completed. Thus, the A/D conversion is stopped
temporarily and conversion data is not stored in the A/D data register (ADCR0/
ADCR1).
When data transfer of the last piece of data to memory is completed, this bit is
cleared to "0" and the A/D conversion is then restarted.
Note:
This bit is valid when EI2OS is used.
bit11
bit10
STS1, STS0:
A/D activation
select bit
These bits select how A/D conversion is to be activated.
When two or more activation causes are shared, activation is the result of the
cause that occurs first.
Note:
Change the setting during A/D conversion only while there is no corresponding
activation cause, since the change becomes effective immediately.
bit9
STRT:
A/D conversion
activation bit
This bit allows software to start A/D conversion.
Writing 1 to this bit activates A/D conversion.
In stop conversion mode, conversion cannot be reactivated with this bit.
The value read from this bit is "1".
Note:
Never perform the forced stop and activation (BUSY="0", STRT="1") of the A/D
conversion simultaneously.
bit8
RESV:
Reserved bit
Note:
Always write 0 to this bit.