Renesas M16C/64A Series User Manual page 824

M16C/64A Group
32.21.10 Repeat Mode, Repeat Sweep Mode 0, and Repeat Sweep Mode 1
In repeat mode, repeat sweep mode 0, and repeat sweep mode 1, when reading the ADi register (i = 0
to 7) during the period when the ADi register value is rewritten, an undefined value may be read. Read
the ADi register several times to determine whether the read value is valid. The period for reading an
undefined value is one cycle of fAD.
A/D conversion
AD0 register
AD1 register
AD7 register
The above diagram assumes the following:
•
Bits MD1 to MD0 in the ADCON0 register are 11b, and the MD2 bit in the ADCON1 register is 0
(repeat sweep mode 0).
•
Bits ADGSEL1 to ADGSEL0 in the ADCON2 register are 00b (AN0 to AN7 groups selected).
•
Bits SCAN1 to SCAN0 in the ADCON1 register are 11b (AN0 to AN7 (8 pins) selected).
Figure 32.18 Period When the ADi Register Value is Rewritten
R01UH0136EJ0210 Rev.2.10
Jul 31, 2012
AN0 AN1 AN2
One cycle of fAD One cycle of fAD
The AD0 register is rewritten during this period.
When reading the AD0 register during this period,
an undefined value is read.
AN7 AN0
One cycle of fAD One cycle of fAD
32. Usage Notes
AN1
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