Sony Ericsson GM47 - Manual (Page 57)

2. SYSTEM CONNECTOR INTERFACE
57
LZT 123 7263 R1C
RTS and CTS are capable of transmitting at 1/10th of the data
transmission speed for data rates up to 460kbit/s (byte-oriented flow
control mechanism).
Note! When hardware flow control is not used in communications between
the application and the module, RTS and CTS must to be connected to
each other at the module.
Switching times for RTS and CTS
The table below shows the switching times.
Request to Send (RTS)
Used to condition the DCE for data transmission. The default level is
high by internal pull up.
The application must pull RTS low to enable data transmission from the
module. Similarly, the module asserts CTS low, indicating it is ready to
receive data transmission from the host.
Clear To Send (CTS)
CTS is asserted by the DCE to indicate that the host (DTE) may transmit
data. When CTS is high, the host (DTE) is not permitted to transmit
data.
The table below shows the load characteristics for this signal.
Parameter Limit
Time from Low to High level < 2µs
Time from High to Low level < 2µs
Parameter Limit
Application driving impedance <100 Ω
Input capacitance <2nF
Input resistance (pull-up) 100k Ω to VCC
Parameter Limit
Application load capacitance <500pF
Application load resistance ≥1M Ω