Table of Contents
Advertisement
CHAPTER 13 8/10-BIT A/D CONVERTER
[Bit 14, 13] ST1, ST0 (Sampling time setting bits)
•
These bits are used for selecting the A/D conversion sampling time.
•
After A/D conversion is started, analog input is acquired for the time specified by these bits.
Note:
When 00 for 8 MHz is specified when 16-MHz operation is used, analog voltages may not be
correctly acquired.
[Bit 12, 11] CT1, CT0 (Comparison time setting bit)
•
These bits are used to select the comparison time for A/D conversion.
•
After analog input is acquired (the sampling time elapses) and the time specified by these
bits elapses, the converted data is fixed and stored in bit 9 to bit 0 of this register.
Note:
when 00 for 8 MHz is specified in cases where 16-MHz operation is used, the A/D converted
value may not be correctly obtained.
[Bit 10]
Unused bit
[Bits 9 to 0] D9 to D0
•
The result of A/D conversion is stored. The content of this register is rewritten every time
conversion is completed.
•
Normally, the final value of conversion is stored.
•
The initial value of this register is undetermined.
Note:
The device has a function for saving converted data.
Do not write these bits during A/D conversion.
Notes:
•
Be sure to rewrite the S10 bit during a stop of the A/D conversion operation and before the
conversion operation is restarted. When the S10 bit is rewritten after conversion, the content
of the ADCR becomes unknown.
•
When the 10-bit mode is specified, be sure to use the word transfer command to read data
from the ADCR register.
288
Advertisement
Table of Contents
