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RX230 Group, RX231 Group
Initial Settings and Usage Procedure of RTC Battery Backup Function
R01AN4831EJ0100 Rev.1.00
Page 11 of 23
Aug.20.19
Figure 2.2 Excerpt from RSKRX231
User’s Manual
Figure 2.3 VBATT Circuit Detail Excerpted from RSKRX231 CPU Board Schematics
2.5.2 RTCIC1 Input
The RX231 RSK board is designed SW1 for IRQ1 (RTCIC1) input and
it is set to “pull-up by VCC.” It is
therefore necessary to make the following modifications.
1. Remove resistor R271.
2. Connect IRQ1 to VBATT battery through an external switch.
3. When the switch is turned on, VBATT is connected to IRQ1.
For reference when performing modifications, see Figure 2.4, RTCIC1 Circuit Detail Excerpted from
RSKRX231 CPU Board Schematics.
GROUND
Figure 2.4 RTCIC1 Circuit Detail Excerpted from RSKRX231 CPU Board Schematics