DR8000 Datasheet, PDF (5/7 Pages) Murata Manufacturing Co., Ltd. – 916.50 MHz Transceiver Module

Theory of Operation
The DR8000 evaluation module is centered around the TR8000
ASH Transceiver. The DR8000 may operate in backward
compatible 2G mode, or in the enhanced 3G mode. Since 3G mode
requires the use of a serial I/O port to configure internal registers,
the module includes an on-board Silicon Labs C8051F330
microcontroller to control access to the serial port. When 2G mode
is enabled the microcontroller serves no function. When 3G mode
is enabled the microcontroller constantly scans pins 8-15 for a
change of logic state. When a state change is detected on one or
more of these pins, the microcontroller automatically updates the
internal configuration registers via the serial port of the TR8000.
The microcontroller assumes full control of the CFG pin, CFGCLK
pin, and CFGDAT pin in 3G mode to continuously update the
internal registers.
The DR8000 module is designed to demonstrate the performance
of the TR8000 ASH Transceiver at 4.8kbps, although other data
rates are possible with changes in on-board component values.
See pin descriptions and refer to the TR8000 datasheet.
The DR8000 module may be mounted on a prototype assembly
using standard 0.1” spacing, 10-pin headers spaced 0.9” apart.
2G Mode Operation
The DR8000 may operate in 2G mode. See pin 15 description and
Power-up Mode Select (J2) section for mode select details. In 2G
mode, the CFGCLK pin (18) and CFGDAT pin (17) operate as
CTRL0 and CTRL1, respectively, just as for second-generation
devices. The CFGCLK and CFGDAT pins are a high impedance
input allowing external control for 2G configuration. The logic levels
on CFGCLK (CTRL0) and CFGDAT (CTRL1) control the default 2G
operation as shown below:
CFGCLK (CNTRL0)
0
1
0
1
CFGDAT (CNTRL1)
0
0
1
1
MODE
SLEEP
TX OOK
TX ASK
RX
J5 Header
Current Consumption Monitor (J5)
The current consumption of the TR8000 device may be monitored
by removing J5 and connecting an ammeter across the terminals.
When J5 is removed it isolates the TR8000 from VCC powering the
on-board processor to give a true reading of the current
consumption of only the TR8000 without the additional current
usage of the processor. J5 must be installed to power the TR8000
if not using the header for current measurement.
Power-up Mode Select (J2)
J2 is used to select the operating mode of the TR8000 device only
at power-up. The state of J2 when VCC is applied will determine
whether the board operates in 2G mode or 3G mode. Pin 2 (center
pin) of J2 is connected to Pin 19 (CFG) of the TR8000 device and
is grounded for 2G mode and functions as the chip select line for the
serial interface in 3G mode. Installing the jumper will either connect
the CFG pin of the TR8000 to GND or directly to the processor for
control in 3G mode. See the table below for power-up jumper
settings.
Setting
J2(1-2)
J2(2-3)
Power-up Mode
2G
3G
Pin 19
Connected to GND
Connected to Processor
After power-up if 3G mode is selected, pin 15 (3G Sel) must be
pulled ‘High’ to initiate the processor to operate in 3G mode. Failure
to pull pin 15 ‘High’ after power-up will cause the processor to
remain inactive.
J4
J2 Header
Programming Header (J4)
The programming header allows for custom firmware development
for the Silicon Labs C8051F330 if desired. Contact RFM for more
information about custom firmware development.
www.RFM.com E-mail: [e-mail]
©2008 by RF Monolithics, Inc.
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DR8000 - 4/8/08