Transmit Register [POR=B8AAh]
Bit Bit Bit Bit Bit Bit Bit Bit Bit Bit Bit Bit Bit Bit Bit Bit
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
1 0 1 1 1 0 0 0 TX7 TX6 TX5 TX4 TX3 TX2 TX1 TX0
The Transmit Register holds the 8 bits to be transmitted. Bit [7] of the Configuration Register must be set
(logic ‘1’) in order to use this. If Bit [7] is not set, use pin 6 to manually modulate the data.
The initial value of the register is AAh. This can be used to send a preamble signal by setting Bit [5] of
the Power Management Register (See Figure 3 below). When this bit is set, transmission begins
immediately and the initial value AAh is sent. The SDO pin(4) may be monitored to see when the next
byte of data may be written to the register (SDO is logic ‘1’).
Initial Setup
TXEN = 0
FIGURE 6. Initial TX Register Setting
Bit [15..8] - Command Code: These bits are the command code that is sent serially to the processor that
identifies the bits to be written to the Transmit Register.
Bit [7..0] – Transmit Byte: The data byte to be sent is written here. As soon as the power amplifier is
enabled the data byte is sent. The SDO pin(4) may be monitored to determine when the byte has been
sent.
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