2.6 10-Bit 8-Input Channel A/D Converter (with 8-bit Resolution Mode)
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Chapter 2: Hardware
[Bit 13] INTE (Interrupt enable)
This bit enables/disables the interrupt when conversion ends.
0: Interrupt disabled
1: Interrupt enabled
This bit should always be set when using I2OS functions. I2OS provided with the ability to be
initiated with the interrupt requests.
This bit is initialized to ‘0’ at a reset.
[Bit 12] PAUS (A/D converter pause)
This bit is set when the A/D conversion operation is temporarily stopped.
Because the A/D converter has only one register in which to store the results of conversion, the last
data will be lost in continuous conversion mode unless the results of the last conversion have
already been read by the CPU. Therefore continuous conversion mode requires the system settings
for the use of I2OS to automatically transfer the conversion results to memory as soon as each
conversion is completed.
Note that it is possible for cases such as multiple interrupts to keep the existing conversion data from
being transferred before new data is produced by the next conversion cycle. This bit provides a
preventive function designed to handle such cases, by which this bit is set during the interval
between the end of conversion and the transfer of the data register contents by I2OS. During that
interval A/D conversion is stopped so that no new conversion data is stored. Once the transfer is
completed by I2OS, the A/D converter automatically resumes conversion processing. This register is
therefore valid only when using I2OS functions. This bit is initialized to ‘0’ at a reset.
[Bits 11, 10] STS1, STS0 (Start source select)
The value of these bits determines the A/D conversion start source. These bits are initialized to ‘00’
at a reset.
Table 2.6.1 STS Bit Settings
In modes with more than one start source, A/D conversion will be started by the first source to
occur. Because the start sources are changed immediately when bit settings are changed, settings
may be changed during A/D operation only when the intended conversion start source is not present.
When the external trigger input level is ‘L,’ STS bits can be set to start A/D conversion from
external pin trigger sources.
[Bit 9] STRT (Start)
Write ‘1’ to this bit to start A/D conversion. To restart conversion, write ‘1’ to this bit again. No
restart may be applied in stop mode. This bit is initialized to ‘0’ at a reset.
[CAUTION]
Do not execute a forced stop and software start (BUSY=0, STRT=1) simultaneously.
STS1
STS0
Function
0
Software start
0
1
External pin trigger start and software start
1
0
Multi-function timer start and software start
1
External pin trigger start, multi-function timer start and software start