M32C8A Datasheet, PDF (55/372 Pages) Renesas Technology Corp – RENESAS MCU M16C FAMILY / M32C/80 Series

M32C/8A Group
6. Power Supply Voltage Detection Function
Voltage Detection Register 1
b7 b6 b5 b4 b3 b2 b1 b0
0000 000
Symbol
VCR1
Address
001Bh
After Reset
0000 1000b
Bit Symbol
Bit Name
Function
RW
−
(b2-b0)
Reserved bits
Set to 0
RW
VC13
Voltage change monitor flag⁽¹⁾
0: VCC1 < Vdet4
1: VCC1 ≥ Vdet4
RO
−
(b7-b4)
Reserved bits
Set to 0
RW
NOTE:
1. The VC13 bit is enabled when the VC27 bit in the VCR2 register is set to 1 (Vdet4 detection function used).
The VC13 bit becomes 1 when the VC27 bit is set to 0 (Vdet4 detection function not used).
Voltage Detection Register 2⁽¹⁾
b7 b6 b5 b4 b3 b2 b1 b0
000000
Symbol
VCR2
Address
0017h
After Reset
00h
Bit Symbol
Bit Name
Function
RW
−
(b5-b0)
Reserved bits
Set to 0
RW
VC26
Vdet3 detection function
select bit^{(2, 4, 5)}
0: Vdet3 detection function not used
1: Vdet3 detection function used
RW
VC27
Vdet4 detection function
select bit^{(3, 4)}
0: Vdet4 detection function not used
1: Vdet4 detection function used
RW
NOTES:
1. Set the VCR2 register after the PRC3 bit in the PRCR register is set to 1 (write enable).
2. To use the hardware reset 2 (Vdet3 detection function), set the VC26 bit to 1.
3. To use the Vdet4 detection function, set the VC27 bit to 1 and the D40 bit in the D4INT register to 1 (Vdet4 detection interrupt
used). The VC13 bit in the VCR1 register and the D42 bit in the D4INT register are enabled when the VC27 bit is set to 1.
4. After the VC26 or VC27 bit is set to 1, the detection circuit waits for td(E-A) to elapse before starting operation.
5. The VC26 bit is disabled when the MCU is in stop mode. (The hardware reset 2 is not performed even if the voltage applied to
the VCC1 pin drops below Vdet3.)
Figure 6.2 VCR1 Register, VCR2 Register
Rev.1.00 Jul 15, 2007 Page 38 of 352
REJ09B0385-0100