Figure 14.7 Sample Receive Abort Processing Flowchart (2); Figure 14.8 Receive Abort And Transmit Start (Transmission/Reception Switchover) Timing - Renesas H8S/2111B Hardware Manual

Processing 1
Receive operation ends
normally
Receive data processing
Clear KBF flag
(KCLK = High)
Transmit enabled state.
If there is transmit data, the data is transmitted.

Figure 14.7 Sample Receive Abort Processing Flowchart (2)

Reception in progress
KCLK
(pin state)
KD
(pin state)
KCLK
(input)
KCLK
(output)
KD
(input)
KD
(output)
Rev. 1.00, 05/04, page 360 of 544
[1]
Keyboard side monitors clock during
receive operation (transmit operation
as seen from keyboard), and aborts
receive operation during this period.
Receive abort request
Figure 14.8 Receive Abort and Transmit Start
(Transmission/Reception Switchover) Timing
[1] On the system side, drive the KCLK pin low, setting
the I/O inhibit state.
Transmit operation
Start bit