XB24-PDK Digi International/Maxstream, XB24-PDK Datasheet - Page 58

• Manufacturer Part Number: XB24-PDK
• Description: KIT DEV PRO ZIGBEE
• Manufacturer: Digi International/Maxstream
• Series: XBee™r
• Type: 802.15.4/Zigbeer

Specifications of XB24-PDK

• Frequency: 2.4GHz
• For Use With/related Products: Xbee-PRO Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

XBee®/XBee‐PRO® RF Modules ‐ 802.15.4 ‐ v1.xEx [2009.09.23]
Start Delimiter
(Byte 1)
0x7E
Start Delimiter
0 x7E
API Types
Checksum
Modem Status
MSB
Data bytes that need to be escaped:
Note: In the above example, the length of the raw data (excluding the checksum) is 0x0002 and
the checksum of the non-escaped data (excluding frame delimiter and length) is calculated as:
0xFF - (0x23 + 0x11) = (0xFF - 0x34) = 0xCB.
To test data integrity, a checksum is calculated and verified on non-escaped data.
To calculate: Not including frame delimiters and length, add all bytes keeping only the lowest 8
bits of the result and subtract from 0xFF.
To verify: Add all bytes (include checksum, but not the delimiter and length). If the checksum is
correct, the sum will equal 0xFF.
Frame data of the UART data frame forms an API-specific structure as follows:
Figure 3‐03. UART Data Frame & API‐specific Structure:
The cmdID frame (API-identifier) indicates which API messages will be contained in the cmdData
frame (Identifier-specific data). Refer to the sections that follow for more information regarding
the supported API types. Note that multi-byte values are sent big endian.
API Identifier: 0x8A
RF module status messages are sent from the module in response to specific conditions.
Figure 3‐04. Modem Status Frames
Example - Raw UART Data Frame (before escaping interfering bytes):
0x11 needs to be escaped which results in the following frame:
0x7E 0x00 0x02 0x23 0x7D 0x31 0xCB
© 2009 Digi Internatonal, Inc.
(Bytes 2-3)
• 0x7E – Frame Delimiter
• 0x7D – Escape
• 0x11 – XON
• 0x13 – XOFF
Length
MSB
Length
LSB
API Identifier
0x7E 0x00 0x02 0x23 0x11 0xCB
LSB
cmdID
API Identifier
0x8 A
API-specific Structure
API -specific Structure
Frame Data
(Bytes 4- n)
0 = Hardware reset
1 = W atchdog timer reset
2 = Associated
3 = Disassociated
4 = Synchronization Lost
5 = Coordinator realignment
6 = Coordinator started
Frame Data
Identifier-specific Data
( Beacon -enabled only )
Identifier-specific Data
cmdData
Status (Byte 5 )
cmdData
(Byte n + 1)
Checksum
1 Byte
Checksum
1 Byte
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