Flags Showing The Status Of Csio Receive Operation - Renesas M32R/ECU Series User Manual

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12.4.5 Flags Showing the Status of CSIO Receive Operation

There are following flags that indicate the status of receive operation during CSIO mode:
• SIO Receive Control Register receive status bit
• SIO Receive Control Register reception finished bit
• SIO Receive Control Register receive error sum bit
• SIO Receive Control Register overrun error bit
When reading the content of the SIO Receive Buffer Register after reception is completed, if the serial I/O
finishes receiving the next data before the previous data is not read out, an overrun error occurs and the subse-
quent received data are not transferred to the receive buffer register.
Before receive operation can be restarted, the receive enable bit must temporarily be cleared to "0" to initialize
the receiver control unit.
The above reception finished bit, if no receive errors occurred (Note 1), may be cleared by reading out the lower
byte of the SIO Receive Buffer Register or clearing the REN (Receive Enable) bit.
However, if any receive error occurred, the reception finished bit can only be cleared by clearing the REN
(Receive Enable) bit, and cannot be cleared by reading out the lower byte of the SIO Receive Buffer Register.
Note 1: Overrun errors are the only error that can be detected during reception in CSIO mode.
12.4 Receive Operation in CSIO Mode
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Serial I/O
32180 Group User's Manual (Rev.1.0)