Notes On A/D Converter - Renesas R8C Series User Manual

R8C/1A Group, R8C/1B Group
17.8

Notes on A/D Converter

• Write to each bit (other than bit 6) in the ADCON0 register, each bit in the ADCON1 register, or the SMP bit
in the ADCON2 register when A/D conversion is stopped (before a trigger occurs).
• When the VCUT bit in the ADCON1 register is changed from 0 (VREF not connected) to 1 (VREF
connected), wait for at least 1 µs before starting A/D conversion.
• After changing the A/D operating mode, select an analog input pin again.
• When using the one-shot mode, ensure that A/D conversion is completed before reading the AD register. The
IR bit in the ADIC register or the ADST bit in the ADCON0 register can be used to determine whether A/D
conversion is completed.
• When using the repeat mode, use the undivided main clock as the CPU clock.
• If the ADST bit in the ADCON0 register is set to 0 (A/D conversion stops) by a program and A/ D conversion
is forcibly terminated during an A/D conversion operation, the conversion result of the A/D converter will be
undefined. If the ADST bit is set to 0 by a program, do not use the value of the AD register.
Rev.1.30 Dec 08, 2006
REJ09B0252-0130
Page 244 of 315
17. A/D Converter