TDK blu2i 用户手册

Notes: 
 

•  UART_RX, UART_TX, UART_CTS, UART_RTS, UART_RI, 

UART_DCD and UART_DSR are all 3.3v level logic. For example, 
when RX and TX are idle they will be sitting at 3.3V. Conversely 
for handshaking pins CTS, RTS, RI, DCD, DSR a 0v is treated as 
an assertion. 

 

•  Pin 6 (UART_RI) is active low. It is normally 3.3v. When a remote 

device initiates a connection, this pin goes low. This means that 
when this pin is converted to RS232 voltage levels it will have the 
correct voltage level for assertion. 

 

•  Pin 8 (UART_DCD) is active low. It is normally 3.3v. When a 

connection is live this pin is low. This means that when this pin is 
converted to RS232 voltage levels it will have the correct voltage 
level for assertion. 

 

•  Pin 10 (UART_DSR) is an input, with active low logic. It should be 

connected to the DTR output of the host. When the blu

2i

 Module is 

in high speed mode (See definition for S Register 512), this pin 
should be asserted by the host to ensure that the connection is 
maintained. A deassertion is taken to mean that the connection 
should be dropped, or an online command mode is being 
requested. 

 

•  The GPIOn pins can be accessed using S Registers 621 to 625 

 

•  GPIO4 and GPIO5 are also connected to LEDs on the module. If 

these I/O pins are set for input, then the LED will be driven by the 
host and appropriate drive current requirements must be satisfied. 
By default GPIO4 is used to drive the right LED which indicates 
connection status. A Logic 1 switches on the LED. 

 

•  Analogue 0 and 1 should not exceed 1.8v and S Registers 7xx are 

used to access them. 

 

•  GPIO3 is used for DTR output (active low). 

 
 

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