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DNT24 Integration Guide - 10/19/11
Transparent data is routed using a
remote transparent destination address
. In a remote, this address
defaults to the base, 0x000000, and in the base this address defaults to broadcast, 0xFFFFFF. These
defaults can be overridden with specific radio addresses. For example, it is possible to set up transparent
peer-to-peer routing between two remotes in a point-to-multipoint or store-and-forward system by loading
specific MAC addresses in each radio’s remote transparent destination address.
3.0 DNT24 Application Interfaces
A DNT24 module provides a variety of application interfaces including two serial ports, an SPI port, six
digital I/O ports (logic state), three 12-bit ADC input ports, and two 12-bit DAC output ports. Each of these
interfaces is discussed below.
3.1 Serial Ports
The DNT24 includes two serial ports, one for communication and an optional one for diagnostics. The
communication port is a full-duplex UART interface with hardware flow control on two of the digital I/O
pins as an optional feature. One digital I/O pin can also be configured as an RS485 enable function. The
serial communication port can be configured with baud rates from 1.2 to 250.0 kbps, with 9.6 kbps the
default baud rate. The DNT24 communication port transmits/receives 8-bit data with a choice of even,
odd or no parity and 1 or 2 stop bits. The default configuration is no parity and one stop bit. See Section
5.1 for recommendations on configuring the communication port, and Section 7.4.4 for detailed informa-
tion on configuration parameters. The diagnostic port is enabled as an alternate function on two digital I/O
pins, and can be configured with baud rates from 1.2 to 250.0 kbps, with 9.6 kbps the default baud rate.
The diagnostic port transmits/receives 8-bit data with no parity and 1 stop bit. See Section 7.4.8 for diag-
nostic port configuration details.
3.2 SPI Port
The DNT24 serial peripheral interface (SPI) port can operate either as a master or a slave. The port
includes the four standard SPI connections - MISO, MOSI, SCLK and /SS, plus three signals used to
support SPI slave mode operation - /HOST_RTS, /HOST_CTS and DAV. The serial port and SPI master
mode can run simultaneously. Serial port operation is disabled when the SPI port is configured for slave
mode. Note that all SPI slave mode messages must be protocol formatted.
D N T 9 0 0
P e r i p h e r a l
D N T 2 4 S P I M a s t e r M o d e S i g n a l i n g
/ S S
S C L K
M O S I
M I S O
Figure 3.2.1
