
26 SuPPlY VOlTaGe DeTeCTOR (SVD)
S1C17624/604/622/602/621 TeChniCal Manual
Seiko epson Corporation
26-3
To use this interrupt, set SVDIE/SVD_IMSK register to 1. When SVDIE is set to 0 (default), interrupt requests
for this cause will not be sent to the interrupt controller (ITC).
If SVDIF is set to 1 while SVDIE is set to 1 (interrupt enabled), the SVD module outputs an interrupt request to
the ITC. An interrupt is generated if the ITC and S1C17 Core interrupt conditions are satisfied.
For more information on interrupt processing, see the “Interrupt Controller (ITC)” chapter.
notes: • To prevent interrupt recurrences, the SVD module interrupt flag SVDIF must be reset in the
interrupt handler routine after an SVD interrupt has occurred.
• To prevent unwanted interrupts, SVDIF should be reset before enabling SVD interrupts with
SVDIE.
Control Register Details
26.6
6.1 List of SVD Registers
Table 26.
address
Register name
Function
0x5066
OSC_SVD
SVD Clock Control Register
Selects the operating clock.
0x5100
SVD_EN
SVD Enable Register
Enables/disables the SVD operation.
0x5101
SVD_CMP
SVD Comparison Voltage Register
Sets the comparison voltage.
0x5102
SVD_RSLT
SVD Detection Result Register
Voltage detection results
0x5103
SVD_IMSK
SVD Interrupt Mask Register
Enables/disables interrupts.
0x5104
SVD_IFLG
SVD Interrupt Flag Register
Indicates/resets interrupt occurrence status.
The SVD module registers are described in detail below. These are 8-bit registers.
note: When data is written to the registers, the “Reserved” bits must always be written as 0 and not 1.
SVD Clock Control Register (OSC_SVD)
Register name address
Bit
name
Function
Setting
init. R/W
Remarks
SVD Clock
Control Register
(OSC_SVD)
0x5066
(8 bits)
D7–2 –
reserved
–
–
–
0 when being read.
D1
SVDSRC
SVD clock source select
1 OSC1
0 HSCLK/512
1
R/W
D0
SVDCKen SVD clock enable
1 Enable
0 Disable
0
R/W
D[7:2]
Reserved
D1
SVDSRC: SVD Clock Source Select Bit
Selects the clock source for the SVD circuit.
1 (R/W): OSC1 (default)
0 (R/W): HSCLK/512
When OSC1 is selected as the clock source, the OSC1 clock (typ. 32.768 kHz) is directly used as SVD-
CLK. When HSCLK is selected as the clock source, SVDCLK is generated by dividing HSCLK (IOSC
or OSC3 clock) by 512.
D0
SVDCKen: SVD Clock enable Bit
Enables or disables the operation clock supply to the SVD circuit.
1 (R/W): Enabled (on)
0 (R/W): Disabled (off) (default)
The SVDCKEN default setting is 0, which disables the clock supply. Setting SVDCKEN to 1 feeds the
clock selected to the SVD circuit.
SVD enable Register (SVD_en)
Register name address
Bit
name
Function
Setting
init. R/W
Remarks
SVD enable
Register
(SVD_en)
0x5100
(8 bits)
D7–1 –
reserved
–
–
–
0 when being read.
D0
SVDen
SVD enable
1 Enable
0 Disable
0
R/W
D[7:1]
Reserved