Operations; Operational Design; Uart - Digi XLR PRO User Manual

Operations

Operational design

The XLR PRO RF Module uses a multi-layered firmware base for data flow. The flow of data depends
on the hardware and software configuration you choose. The configuration block diagram below
shows the host serial interface as the physical starting point and the antenna as the physical endpoint
for transferred data. As long as an interface block is able to touch another block above or below, the
two interfaces can interact. For example, if the XLR PRO RF Module is using API mode, Transparent
Mode is not available.

UART

The following parameters must be configured to match the host device:
BD: Baud rate (See the AT command table for limits)
n
NB: Parity (None, Even, or Odd)
n
SB: Stop bits (1 or 2)
n
UART connections support hardware flow control using CTS and RTS and requires matching
parameters on the XLR PRO and the host device. This includes the following:
D6: RTS flow control. If enabled, then XLR PRO will not output data unless RTS is asserted. The
n
host device should not de-assert RTS for long periods of time to avoid filling the serial transmit
buffer. If an RF data packet is received, and the serial transmit buffer does not have enough
space for all of the data bytes, the entire RF data packet will be discarded.
D7: CTS flow control. If enabled, then XLR PRO will not assert CTS low unless it can handle
n
more data from the host.
XLR PRO Radio Frequency (RF) Module User Guide

Operational design

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