Honeywell ISA100 Gen X User Manual page 30

The packet type is dependent on the packet class (refer to section . When the TLDE flushes the
contract ID 0 from the ASL queue, it is converted to an ASL indication and it is sent to the
Sensor board when it acquires its priority APDU.
ASL Queued Packet Types and Stack Specific Packet Types for details).
Packet ID
The packet ID identifies specific packets across the network. It checks for missed packets on
the SPI interface.
Packet Data Length
The data length byte specifies the number of data bytes that are sent in this packet. You can
check the packet length with the number of bytes transferred to verify whether the entire
packet is transferred.
IPC Data Classes
The two packet classes supported are: ASL packets and Stack specific.
ASL queued packets class = 0x00
Stack specific class = 0x30 or 0x38
ASL Queued Packets
ASL queued packet class provides pass through access to the ASL queue located on the Radio
board. This class of data packets allows prioritization and coordination of the Sensor packets
with any Radio packets that are also queued. By using the ASL queue packets sent from the
Sensor, the UAP can utilize concatenation and other functions that are not possible if simple
Tx and Rx buffers are implemented and no ASL queue is implemented in the Sensor. In
addition, ASL queue packets allow coordination of notification for contract errors as well as
network retry.
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ISA100 Gen X Radio Module User's Guide
Honeywell
Release Independent
April 2018