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BB-ZP9D115RMLR-A Radio Modem
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API OPERATION
By default, BB-ZP9D115RMLR-A Radio Modem acts as a serial line replacement
(Transparent Operation) - all UART data received through the DI pin is queued up for RF
transmission. When the module receives an RF packet, the data is sent out the DO pin with
no additional information.
Inherent to Transparent Operation are the following behaviors:
• If module parameter registers are to be set or queried, a special operation is
required for transitioning the module into Command Mode [refer to p17].
• In point-to-multipoint systems, the application must send extra information so that
the receiving module(s) can distinguish between data coming from different
remotes.
As an alternative to the default Transparent Operation, API (Application Programming
Interface) Operations are available. API operation requires that communication with the
module be done through a structured interface (data is communicated in frames in a
defined order). The API specifies how commands, command responses and module status
messages are sent and received from the module using a UART Data Frame.
API FRAME SPECIFICATIONS
Two API modes are supported and both can be enabled using the AP (API Enable)
command. Use the following AP parameter values to configure the module to operate in a
particular mode:
• AP = 0 (default): Transparent Operation (UART Serial line replacement)
API modes are disabled.
• AP = 1: API Operation
• AP = 2: API Operation (with escaped characters)
Any data received prior to the start delimiter is silently discarded. If the frame is not
received correctly or if the checksum fails, the data is silently discarded.
API Operation (AP parameter = 1)
When this API mode is enabled (AP = 1), the UART data frame structure is defined as
follows:
UART Data Frame Structure:
MSB = Most Significant Byte, LSB = Least Significant Byte