SAB80515 Datasheet, PDF (75/270 Pages) Siemens Semiconductor Group – 8-Bit Single-Chip Microcontroller Family

On-Chip Peripheral Components
Table 7-6
Selection of the Analog Input Channels
MX2
MX1
MX0
Selected Channel
0
0
0
Analog input 0
0
0
1
Analog input 1
0
1
0
Analog input 2
0
1
1
Analog input 3
1
0
0
Analog input 4
1
0
1
Analog input 5
1
1
0
Analog input 6
1
1
1
Analog input 7
MYMOS
AN0
AN1
AN2
AN3
AN4
AN5
AN6
AN7
Pin
ACMOS
P6.0
P6.1
P6.2
P6.3
P6.4
P6.5
P6.6
P6.7
The bits MX0 to MX2 in special function register ADCON are used for selection of the analog input
channels.
Port 6 of the ACMOS versions is a dual purpose input port. lf the input voltage meets the specified
logic levels, it can be used as digital input as well regardless of whether the pin levels are sampled
by the A/D converter at the same time.
The special function register ADDAT (figure 7-28) holds the converted digital 8-bit data result. The
data remains in ADDAT until it is overwritten by the next converted data. ADDAT can be read or
written under software control. lf the A/D converter of the SAB 80(C)515 is not used, register
ADDAT can be used as an additional general purpose register.
Figure 7-28
Special Function Register ADDAT (Address 0D9H)
0D9H
Conversion result
This register contains the 8-bit conversion result.
ADDAT
7.4.1.2 Start of Conversion
An internal start of conversion is triggered by a write-to-DAPR instruction. The start procedure itself
is independent of the value which is written to DAPR. However, the value in DAPR determines
which internal reference voltages are used for the conversion (see section 7.4.2).
When single conversion mode is selected (ADM = 0) only one conversion is performed. In
continuous mode after completion of a conversion a new conversion is triggered automatically, until
bit ADM is reset.
Semiconductor Group
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