C515A_9708 Datasheet, PDF (113/182 Pages) Siemens Semiconductor Group – 8-Bit CMOS Microcontroller

On-Chip Peripheral Components
C515A
Special Function Registers ADCON0 (Address D8H)
Special Function Registers ADCON1 (Address DCH)
Reset Value : 00H
Reset Value : 0XXXX000B
Bit No. MSB
7
6
D8H BD CLK
5
4
ADEX BSY
3
ADM
2
MX2
1
MX1
LSB
0
MX0
ADCON0
DCH ADCL –
–
–
– MX2 MX1 MX0 ADCON1
The shaded bits are not used for A/D converter control.
Bit
–
ADEX
BSY
ADM
MX2 - MX0
Function
Reserved bits for future use
Internal / external start of converrsion
When set, the external start of an A/D conversion by a falling
edge at pin P4.0 / ADST is enabled.
Busy flag
This flag indicates whether a conversion is in progress (BSY = 1).
The flag is cleared by hardware when the conversion is finished.
A/D conversion mode
When set, a continuous A/D conversion is selected. If cleared,
the converter stops after one A/D conversion.
A/D converter input channel select bits
Bits MX2-0 can be written or read either in ADCON0 or ADCON1.
The channel selection done by writing to ADCON 1(0) overwrites
the selection in ADCON 0(1) when ADCON 1(0) is written after
ADCON 0(1).
The analog inputs are selected according the following table :
MX2 MX1 MX0
000
001
010
011
100
101
110
111
Selected Analog Input
P6.0 / AIN0
P6.1 / AIN1
P6.2 / AIN2
P6.3 / AIN3
P6.2 / AIN4
P6.3 / AIN5
P6.4 / AIN6
P6.5 / AIN7
Semiconductor Group
6-62
1997-08-01