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SN8P1700
8-bit micro-controller build-in 12-bit ADC
SONiX TECHNOLOGY CO., LTD
Page 171
Revision 1.93
D/A CONVERTER OPERATION
When the DAENB = 0, the DAO pin is output floating status. After setting DAENB to “1”, the DAO output value is
controlled by DAB bits.
Example: Output 1/2 VDD from DAO pin.
MOV
A,
#00111111B
B0MOV
DAM, A
; Set DAB to a half of the full scale.
B0BSET
FDAENB
; Enable D/A function.
The DAB’s data v.s. DAO’s output voltage as following:
DAB6 DAB5 DAB4 DAB3 DAB2 DAB1 DAB0
DAO
0 0 0 0 0 0 0
VSS
0 0 0 0 0 0 1
Idac
0 0 0 0 0 1 0
2
*
Idac
0 0 0 0 0 1 1
3
*
Idac
. . . . . . .
.
. . . . . . .
.
. . . . . . .
.
1 1 1 1 1 1 0 126
*
Idac
1 1 1 1 1 1 1 127
*
Idac
Table 12-1. DAB and DAO Relative Table
Note: Idac = I
FSO
/ (2
7
-1) (I
FSO
: Full-scale Output Current)