C509-L_97 Datasheet, PDF (186/290 Pages) Siemens Semiconductor Group – 8-Bit CMOS Microcontroller

On-Chip Peripheral Components
C509-L
Special Function Registers ADCON0 (Address D8H)
Special Function Registers ADCON1 (Address DCH)
Reset Value : 00H
Reset Value : 01000000B
Bit No. MSB
7
D8H BD
6
CLK
5
4
ADEX BSY
3
ADM
2
MX2
1
MX1
LSB
0
MX0
ADCON0
DCH ADCL1 ADCL0 ADST1 ADST0 MX3 MX2 MX1 MX0 ADCON1
The shaded bits are not used for A/D converter control.
Bit
ADEX
BSY
ADM
MX3 - MX0
Function
Internal / external start of A/D conversion
When set, the external start of an A/D conversion at pin P6.0/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 during a running
A/D conversion, the conversion is stopped at its end.
A/D converter input channel select bits
Bits MX3-0 can be written or read either in ADCON0 or ADCON1. When writing
to ADCON1, the ADCON0 bits MX2-0 are overwritten. Writing ADCON0, only
MX2-0 are affected.
The analog inputs are selected according the following table:
MX3
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
MX2
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
MX1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
MX0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
Selected Analog Input
P7.0 / AN0
P7.1 / AN1
P7.2 / AN2
P7.3 / AN3
P7.2 / AN4
P7.3 / AN5
P7.4 / AN6
P7.5 / AN7
P8.0 / AN8
P8.1 / AN9
P8.2 / AN10
P8.3 / AN11
P8.4 / AN12
P8.5 / AN13
P8.6 / AN14
Semiconductor Group
6-108
1997-10-01