Renesas RL78/G1P Hardware User Manual page 475

RL78/G1P
(3) SNOOZE mode operation (Abnormal Operation <2>)
Abnormal operation <2> is the operation performed when a communication error occurs while SSECm = 1.
Because SSECm = 1, an error interrupt (INTSREq) is not generated when a communication error occurs.
Figure 11-117. Timing Chart of SNOOZE Mode Operation (Abnormal Operation <2>)
CPU operation status Normal operation STOP mode
SS01
<1>
ST01
SE01
SWC0
EOC01
SSEC0
Clock request signal
(internal signal)
SDR01
RxD0 pin
Shift register 01
INTSR0
L
INTSRE0
TSF01
Note Only read received data while SWCm = 1.
Cautions 1. Before switching to the SNOOZE mode or after reception operation in the SNOOZE mode
finishes, set the STm1 bit to 1 (clear the SEm1 bit, and stop the operation).
And after completion the receive operation, also clearing SWCm bit to 0 (SNOOZE mode
release).
2. When using the SNOOZE mode while SSECm is set to 1, no overrun errors occur. Therefore,
when using the SNOOZE mode, read bits 7 to 0 (RxDq) of the SDRm1 register before
switching to the STOP mode.
Remarks 1. <1> to <9> in the figure correspond to <1> to <9> in Figure 11-118 Flowchart of SNOOZE Mode
Operation (Abnormal Operation <2>).
2. m = 0; q = 0
R01UH0895EJ0100 Rev.1.00
Nov 29, 2019
SNOOZE mode
<4>
<3>
Receive data 1
ST
Shift operation
Data reception
<6>
<2> <5>
CHAPTER 11 SERIAL ARRAY UNIT
SNOOZE mode
STOP mode
Receive data 1
ST Receive data 2
P SP
<6>
<7> <5>
Normal operation
<10>
<11>
<11>
Receive data 2
Note
Read <9>
P SP
Shift operation
Data reception
<7>, <11>
<8>
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