User manual

GRYPHON™ BT CORDLESS READING SYSTEMS
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5 REFERENCES
5.1 USB-COM AND RS232 PARAMETERS
5.1.1 Handshaking
Hardware handshaking: (RTS/CTS)
The RTS line is activated by the cradle before transmitting a character. Transmission
is possible only if the CTS line (controlled by the Host) is active.
RTS
Transmitted data Transmitted data
TX
CTS
Host busy
Signals at
EIA levels
RTS/CTS handshaking
Software handshaking: (XON/XOFF)
During transmission, if the Host sends the XOFF character (13 Hex), the cradle
interrupts the transmission with a maximum delay of one character and only resumes
when the XON character (11 Hex) is received.
Host readyHost busy
XONXOFF
RX
Transmitted dataTransmitted data
TX
XON/XOFF handshaking