AT86RF230 Atmel Corporation, AT86RF230 Datasheet - Page 11

• Manufacturer Part Number: AT86RF230
• Manufacturer: Atmel Corporation

Specifications of AT86RF230

• Crypto Engine: No
• Operating Voltage (vcc): 1.8 to 3.6
• Frequency Band: 2.4 GHz
• Max Data Rate (mb/s): 0.25
• Antenna Diversity: No
• External Pa Control: No
• Power Output (dbm): 3
• Receiver Sensitivity (dbm): -101
• Receive Current Consumption (ma): 16.0
• Transmit Current Consumption (ma): 17.0
• Link Budget (dbm): 104

6.1 SPI Timing Description
Figure 6-2. SPI Timing, Global Map and Definition of Timing Parameters t
Figure 6-3. SPI Timing, Detailed View and Definition of Timing Parameters t
SCLK
MOSI
MISO
5131E-MCU Wireless-02/09
SEL
t
0
t
1
t
3
Bit 7
t
4
Bit 7
The SPI is designed to work in synchronous or asynchronous mode.
In synchronous mode, the CLKM output of the radio transceiver is used as the master
clock of the microcontroller. In this case the maximum SPI clock frequency is 8 MHz.
In asynchronous mode, the SPI master clock (SCLK) is generated by the
microcontroller itself. The maximum SPI clock rate is limited to 7.5 MHz using this
operating mode. If the clock signal from the radio transceiver pin CLKM is not required,
it may be disabled.
Figure 6-2 and Figure 6-3 illustrate the SPI timing and introduce its parameters. The
corresponding timing parameter definition is given in Table 11-4.
The SPI is based on a byte-oriented protocol and is always a bidirectional
communication between master and slave. The SPI master starts the transfer by
asserting SEL = L. Then the master generates eight SPI clock cycles to transfer a byte
to the radio transceiver (via MOSI). At the same time the slave transmits one byte to the
master (via MISO). When the master wants to receive one byte of data from the slave it
must also transmit one byte to the slave. All bytes are transferred MSB first. An SPI
transaction is finished by releasing SEL = H.
A SPI register access consists of two bytes, a Frame Buffer or SRAM access of two or
more bytes, as described in section 6.2.
valid after t
SCLK. If the MISO output driver is disabled, there is no internal pull-up resistor
connected to the output. Driving the appropriate signal level must be ensured by the
SEL = L enables the MISO output driver of the radio transceiver. The MSB of MISO is
t
2
1
(see section 11.4 parameter 11.4.3) and is updated at each falling edge of
Bit 6
Bit 6
5
, t
0
6
, t
to t
8
and t
4
9
Bit 5
Bit 5
AT86RF230
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