Toshiba H1 SERIES TLCS-900 User Manual
Page 153
TMP92CM22
2007-02-16
92CM22-151
Handshake function
Use of
CTS0
pin allows data to be sent in units of one data format; thus, overrun
errors can be avoided. The handshake function is enabled or disabled by the
SC0MOD0<CTSE> setting.
When the
CTS0
pin condition is high level, after completed the current data
transmission, data transmission is halted until the
CTS0
pin state is low again.
However, the INTTX0 interrupt is generated, and it requests the next send from data
to the CPU. The next data is written in the transmission buffer and data transmission
is halted.
Though there is no
RTS
pin, a handshake function can be easily configured by
setting any port assigned to be the
RTS
function. The
RTS
should be output “High” to
request send data halt after data receive is completed by software in the receive
interrupt routine.
Figure 3.9.5 Handshake Function
Note 1: If the
CTS
signal goes high during transmission, will be stop next transmission data after completion of the
current transmission.
Note 2: Transmission starts on the first falling edge of the TXDCLK clock after the
CTS
signal has fallen.
Figure 3.9.6
CTS
(Clear to send) Signal Timing
TXD
CTS
RXD
RTS
(Any port)
TMP92CM22 TMP92CM22
Transmission side
Receiving side
3
13 14 15
16
1
2
SIOCLK
3
14
15 16 1 2
Start bit
Bit0
a
b
Send is suspended
from a to b.
Timing of writing data to
transmission buffer
TXDCLK
TXD
CTS