SENA Promi-ESD02 - Manual (Page 17)

Promi-ESD User Manual – Configurations 17
Copyright © 2006 Sena Technologies, Inc. All rights reserved.
Promi-ESD supports only 8 data bit. In the case of 7 data bit, please contact the
technical support.
 Hardware Flow Control
Promi-ESD plugged into its host system transmits data from host to the other
side Bluetooth device. These data is saved temporarily in the internal buffer of
Promi-ESD and sent repeatedly until the transmission is completed packet by
packet. When the radio transmission condition is not good enough to send data
promptly, it can cause the transmission delay. If the host sends more data when
the buffer is full, buffer overflow will make Promi-ESD malfunction consequently.
In order to prevent this buffer overflow, Promi-ESD works as follows.
In case of using hardware flow control, Promi-ESD makes RTS be ‘disable’ to
stop receiving further data from the host when the buffer becomes full. RTS will
be ‘able’ to begin receiving data again from the host when the buffer has some
room for more data.
In case of not using hardware flow control, Promi-ESD clears the buffer to
secure the room for next data when the buffer becomes full. This means the loss
of data. As the transmission data becomes large, the possibility of data loss goes
higher.
For large data transmission, use of hardware flow control is highly recommended.
If you are not using Hardware flow control (handshaking), please bridge CTS and
GND to disable the function.