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CHAPTER 14 A/D CONVERTER
(2) A/D converter input select register (ADIS)This register determines whether the ANI0/P10 to ANI7/P17 pins should be used for analog input channelsor ports. Pins other than those selected as analog input can be used as input/output ports.ADIS is set with an 8-bit memory manipulation instruction.RESET input sets ADIS to 00H.Cautions 1. Set the analog input channel in the following order. (1) Set the number of analog input channels with ADIS. (2)Using A/D converter mode register (ADM), select one channel to undergo A/Dconversion from among the channels set for analog input with ADIS.2. No internal pull-up resistor can be used to the channels set for analog input with ADIS,irrespective of the value of bit 1 (PUO1) of the pull-up resistor option register L (PUOL).Figure 14-3. A/D Converter Input Select Register Format
0
7
0
6
00
4
ADIS3
3210
FF84H
Address
ADIS
Symbol
ADIS2ADIS1 ADIS0
5
00H
After
Reset
R/W
R/W
ADIS3
0
0
0
0
0
0
0
0
1
Other than above
Number of Analog Input Channel Selection
No analog input channel (P10 to P17)
1 channel (ANI0, P11 to P17)
2 channel (ANI0, ANI1, P12 to P17)
3 channel (ANI0 to ANI2, P13 to P17)
4 channel (ANI0 to ANI3, P14 to P17)
5 channel (ANI0 to ANI4, P15 to P17)
6 channel (ANI0 to ANI5, P16, P17)
7 channel (ANI0 to ANI6, P17)
8 channel (ANI0 to ANI7)
Setting prohibited
ADIS2
0
0
0
0
1
1
1
1
0
ADIS1
0
0
1
1
0
0
1
1
0
ADIS0
0
1
0
1
0
1
0
1
0