Renesas RL78/G15

RL78/G15 CHAPTER 16 RESET FUNCTION
R01UH0959EJ0110 Rev.1.10 Page 643 of 765
Mar 7, 2023
The RESF register is automatically cleared when it is read by an 8-bit memory manipulation instruction.
Figure 16-5 shows the procedure for checking a reset source.
Figure 16-5. Example of Procedure for Checking Reset Source
 Read the RESF register (clear the RESF)
Store the value of the RESF register in any RAM
After reset acceptance
Read RESF register
TRAP of RESF register = 1?
WDTRF of RESF register
= 1?
IAWRF of RESF register
= 1?
SPORF of RESF register = 1?
External reset generated/
power supply voltage dropping below
the lower limit for data retention
Internal reset request by
the execution of the illegal
instruction generated
Yes
No
Internal reset request by
the watchdog timer generated
Yes
No
Internal reset request by
the illegal memory access
generated
Yes
No
Internal reset request by
the SPOR circuit generated
Yes
No
* The flow described above is an example of the procedure for checking.