Three-Wire Interface
Figure 29 shows a different type of three-wire interface with
an 8xC51 microprocessor. Here, the Master Mode is used.
The interface signals consist of SDOUT, SDIO, and SCLK.
Figure 28 shows a three-wire interface with a 8xC32 micro-
processor. Note that the Slave Mode is selected and the
SDIO pin is being used for input and output.
P1.0
8xC32
P1.1
P1.2
P1.3
P1.4
P1.5
P1.6
P1.7
RESET
RXD
TXD
INT0
INT1
AVDD
AIN
AIN
P
N
REFIN
REFOUT
AVDD
1.0µF
AGND
AGND
VBIAS
CS
MODE
DRDY
SDOUT
SDIO
AGND
DGND
ADS1212
DVDD
DSYNC
XIN
XOUT
DGND
SCLK
R1
10kΩ
DVDD
DVDD
T0
T1
WR
RD
X2
DGND
C1
27pF
XTAL
X1
Q
Q
D
Q
Q
D
VSS
C2
27pF
CLK
CLK
1/2 74HC74
1/2 74HC74
FIGURE 28. Three-Wire Interface with a 8xC32 Microprocessor.
P1.0
VCC
P0.0
P0.1
P0.2
P0.3
P0.4
P0.5
P0.6
8xC51
P1.1
P1.2
P1.3
P1.4
P1.5
P1.6
P1.7
AVDD
AIN
P
N
REFIN
REFOUT
AVDD
1.0µF
AGND
DVDD
AIN
AGND
VBIAS
CS
MODE
DRDY
SDOUT
SDIO
AGND
DVDD
ADS1212
C1
6pF(1)
DSYNC
XIN
XTAL
XOUT
DGND
SCLK
R1
10kΩ
DVDD
C2
6pF(1)
DGND
DGND
NOTE: (1) Acceptable capacitive load not to exceed 6pF (±30%).
FIGURE 29. Three-Wire Interface with a 8xC51 Microprocessor.
ADS1212, 1213
31
SBAS064A