Polling Mode (Acknowledged) - Digi XTend User Manual

Polling mode (acknowledged)

Polling mode (acknowledged) and Polling mode (basic) operate in the same way. The difference between the two
modes is in their means of achieving the reliable delivery of data. In Polling mode (acknowledged), the firmware
achieves reliable delivery using retries and acknowledgments.
Characteristics
Constraints
Recommended use
Required parameter
values (Base)
Required parameter
values (Remote)
Related commands
For configuration and theory of operation information, see
Polling Base
XTend RF Module User Guide
Uses a high percentage of available network bandwidth.
Eliminates collisions.
Works with reliable delivery (RR or MT parameters).
Supports binary data transfers.
Base device requests packets from remote device by polling a sequential range of
addresses.
Base device is configured to specify the range of addresses being polled.
Uses inter-character delay to create RF packet lengths aligned with protocol packet
lengths up to 2048 bytes long.
The minimum time interval between polling cycles is configurable. However, if the
remote devices cannot all be processed within that time interval, the polling cycle is
ineffective (i.e. it will impose no additional delay). In order to ensure a pause between
polling cycles, PD must be set to a value which is large enough to accommodate the
pause.
Use for point-to-multipoint applications that require Reliable Delivery of data. Use
this mode when it is critical that a base device be able to discern data coming from
multiple devices.
MD (RF Mode) = 3,
PB (Polling Begin Address)
PE (Polling End Address)
MD (RF Mode) = 4
Networking (RR, PD, DT, MY, AM)
on page 72 and Configure a Polling Remote
Polling mode (acknowledged)
Polling mode theory of operation
on page 72.
on page 72, Configure a
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