NEC V850E/RS1 User Manual page 439

(4) CSIBn status register (CBnSTR)
This is an 8-bit register that indicates the status of CSIB.
Although this register can be read or written in 8-bit or 1-bit units, the CBnSTF flag is read-only.
Reset input clears this register to 00H.
Clearing the CBnPWR bit of the CBnCTL0 register to 0 also initializes this register.
Symbol
CBnSTR CBnTSF
Remark:
CBnTSF
This bit is set when data is prepared in the CBnTX register for transmission. It is set when dummy data is read
from the CBnRX register for reception.
It is cleared when the edge of the last clock is completed.
CBnOVE
• An overrun error occurs if the next reception is started without the CPU reading the value of the receive buffer
during reception or on completion of a reception operation.
• The CBnOVE flag indicates occurrence of this overrun error.
• The OBnOVE flag is cleared when 0 is written to it. It is not set when 1 is written to it.
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Chapter 13 3-Wire Serial Interface (CSIB)
Figure 13-5: CSIBn Status Register (CBnSTR) Format
Address: CB0STR: FFFFFD03H, CB1STR: FFFFFD13H
7 6 5
0 0
n = 0, 1
0 Idle status
1 Operating status
0 No overrun
1 Overrun
User's Manual U16702EE3V2UD00
4 3 2
0 0 0
Transfer operation status flag
Overrun error flag
1 0 R/W After Reset
0 CBnOVE R/W 00H
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