xe8802 Semtech Corporation, xe8802 Datasheet - Page 81

• Manufacturer Part Number: xe8802
• Description: Data Acquisition Soc With 16+10 Bit Zoomingadc? Embedded Risc Controller And Lcd Driver
• Manufacturer: Semtech Corporation

powered with sufficient voltage (see specification below). Below the specified supply voltage, only voltages that are
close to VSS or VBAT can be switched.
When PBAna[x] is set to 1, one pad of the Port B terminals is changed from digital I/O mode to analog. The usage
of the registers RegPBPullup, RegPBOut and RegPBDir define the analog configuration (see Table 12-9).
When PBAna[x] = 1, then PBPullup[x] connects the pin to the analog bus. PBDir[x] and PBPOut[x] select which
of the 4 analog lines is used.
Example:
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Table 12-9: Selection of the analog lines with RegPBDir, RegPBout and RegPBPullup when PBAna[x] = 1
Set the pads PB[2] and PB[5] on the analog line 3. (the values X depend on the configuration of others
pads)
apply high impedance in the analog mode (move RegPBPullup,#0bXX0XX0XX)
go to analog mode (move RegPBAna,#0bXX1XX1XX)
select the analog line3 (move RegPBDir,#0bXX1XX1XX and move RegPBOut,#0bXX1XX1XX)
apply the analog line to the output (move RegPBPullup,#0bXX1XX1XX)
PBDir[x]
analog bus selection
0
0
1
1
X
PBout[x]
X
0
1
0
1
XE8802 Sensing Machine Data Acquisition MCU
12-4
PBPullup[x]
with ZoomingADC™ and LCD driver
1
1
1
1
0
PB[x] selection on
High impedance
analog line 0
analog line 1
analog line 2
analog line 3
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