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SLOS758G – DECEMBER 2011 – REVISED MARCH 2020
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Detailed Description
Copyright © 2011–2020, Texas Instruments Incorporated
6.13 Direct Commands from MCU to Reader
6.13.1 Command Codes
lists the valid commands that the MCU can send to the reader.
Table 6-11. Command Codes
COMMAND
CODE
COMMAND
COMMENTS
0x00
Idle
0x03
Software Initialization
Same as power-on reset
0x0F
Reset FIFO
0x10
Transmission Without CRC
0x11
Transmission With CRC
0x16
Block Receiver
0x17
Enable Receiver
0x18
Test Internal RF
RSSI at RX input with TX off
0x19
Test External RF
RSSI at RX input with TX off
0x1A
Receiver Gain Adjust
The command code values from
are substituted in
, Bits 0 to 4. Also, the most
significant bit (MSB) in
must be set to 1.
Table 6-12. Address/Command Word Bit Distribution
BIT
DESCRIPTION
BIT FUNCTION
ADDRESS
COMMAND
B7
Command control bit
0 = Address
1 = Command
0
1
B6
Read/Write
0 = Write
1 = Read
R/W
0
B5
Continuous address mode
Continuous
mode
Not used
B4
Address/Command bit 4
Adr 4
Cmd 4
B3
Address/Command bit 3
Adr 3
Cmd 3
B2
Address/Command bit 2
Adr 2
Cmd 2
B1
Address/Command bit 1
Adr 1
Cmd 1
B0
Address/Command bit 0
Adr 0
Cmd 0
The MSB determines if the word is to be used as a command or address. The last two columns of
show the function of separate bits depending on whether address or command is written.
Command mode is used to enter a command resulting in reader action (for example, initialize
transmission, enable reader, or turn the reader on or off).
6.13.2 Reset FIFO (0x0F)
The reset command clears the FIFO contents and FIFO Status register (0x1C). It also clears the register
storing the collision error location (0x0E).
6.13.3 Transmission With CRC (0x11)
The transmission command must be sent first, followed by transmission length bytes, and FIFO data. The
reader starts transmitting after the first byte is loaded into the FIFO. The CRC byte is included in the
transmitted sequence.
