Adc And Digital I/O Line Support Of The Xbee/Xbee-Pro Rf Module; I/O Data Format - Digi XBee Product Manual

XBee®/XBee‐PRO® RF Modules ‐ 802.15.4 ‐ v1.xEx

ADC and Digital I/O Line Support of the XBee/XBee-PRO RF Module

I/O Data Format

X X
© 2014 Digi International Inc.
The XBee®/XBee-PRO® RF Modules support ADC (Analog-to-digital conversion) and digital I/O
line passing. The following pins support multiple functions:
Table 2‐01. Pin functions and their associated pin numbers and commands
AD = Analog‐to‐Digital Converter, DIO = Digital Input/Output
Pin functions not applicable to this section are denoted within (parenthesis).
Pin Function
AD0 / DIO0
AD1 / DIO1
AD2 / DIO2
AD3 / DIO3 / (COORD_SEL)
AD4 / DIO4
AD5 / DIO5 / (ASSOCIATE)
DIO6 / (RTS)
DIO7 / (CTS)
DI8 / (DTR) / (Sleep_RQ)
To enable ADC and DIO pin functions:
For ADC Support:
For Digital Input support:
For Digital Output Low support:
For Digital Output High support:
I/O data begins with a header. The first byte of the header defines the number of samples forth-
coming. The last 2 bytes of the header (Channel Indicator) define which inputs are active. Each bit
represents either a DIO line or ADC channel.
Figure 2‐04. Header
Byte 1
Total number of samples
na
bit 15
Sample data follows the header and the channel indicator frame is used to determine how to read
the sample data. If any of the DIO lines are enabled, the first 2 bytes are the DIO sample. The
ADC data follows. ADC channel data is represented as an unsigned 10-bit value right-justified on a
16- bit boundary.
Figure 2‐05. Sample Data
DIO Line Data is first (if enabled)
X X X X X 8 7 6
Pin#
20
19
18
17
11
15
16
12
9
Set ATDn = 2
Set ATDn = 3
Set ATDn = 4
Set ATDn = 5
Header
Bytes 2 - 3 (Channel Indicator)
A5 A4 A3 A2 A1 A0
Bit set to '1' if channel is active
Sample Data
5 4 3 2 1 0 ADCn MSB
AT Command
D0
D1
D2
D3
D4
D5
D6
D7
D8
D8 D7 D6 D5 D4 D3 D2
ADC Line Data
ADCn LSB
D1 D0
bit 0
15