Holtek BS66F340 - Page 84

Rev. 1.60 84 August 20, 2019 Rev. 1.60 85 August 20, 2019
BS66F340/BS66F350/BS66F360/BS66F370
Touch A/D Flash MCU with LED Driver
BS66F340/BS66F350/BS66F360/BS66F370
Touch A/D Flash MCU with LED Driver
LVR
Internal Reset
t
RSTD
+ t
SST
Note: t
RSTD
is power-on delay with typical time=50ms
Low Voltage Reset Timing Chart
• LVRC Register
Bit 7 6 5 4 3 2 1 0
Name LVS7 LVS6 LVS5 LVS4 LVS3 LVS2 LVS1 LVS0
R/W R/W R/W R/W R/W R/W R/W R/W R/W
POR 0 1 0 1 0 1 0 1
Bit 7~0 LVS7~LVS0: LVR voltage select
01010101: 2.1V
00110011: 2.55V
10011001: 3.15V
10101010: 3.8V
Other values: Generates a MCU reset – register is reset to POR value
When an actual low voltage condition occurs, as specied by one of the four dened
LVR voltage value above, an MCU reset will generated. The reset operation will be
activated after 2~3 f
LIRC
clock cycles. In this situation the register contents will remain
the same after such a reset occurs.
Any register value, other than the four dened register values above, will also result in
the generation of an MCU reset. The reset operation will be activated after 2~3 f
LIRC
clock
cycles. However in this situation the register contents will be reset to the POR value.
• RSTFC Register
Bit 7 6 5 4 3 2 1 0
Name — — — — RSTF LVRF LRF WRF
R/W — — — — R/W R/W R/W R/W
POR — — — — 0 x 0 0
"x": unknown
Bit 7~4 Unimplemented, read as "0"
Bit 3 RSTF: Reset control register software reset ag
Described elsewhere.
Bit 2 LVRF: LVR function reset ag
0: Not occurred
1: Occurred
This bit is set to 1 when a specic low voltage reset condition occurs. Note that this bit
can only be cleared to 0 by the application program.
Bit 1 LRF: LVR control register software reset ag
0: Not occurred
1: Occurred
This bit is set to 1 by the LVRC control register contains any undened LVR voltage
register values. This in effect acts like a software-reset function. Note that this bit can
only be cleared to 0 by the application program.
Bit 0 WRF: WDT control register software reset ag
Described elsewhere.