C8051F930-TB Silicon Laboratories Inc, C8051F930-TB Datasheet - Page 200

• Manufacturer Part Number: C8051F930-TB
• Description: BOARD TARGET/PROTO W/C8051F930
• Manufacturer: Silicon Laboratories Inc
• Type: MCUr

Specifications of C8051F930-TB

• Contents: Board
• Processor To Be Evaluated: C8051F930
• Processor Series: C8051F9xx
• Data Bus Width: 8 bit
• Interface Type: I2C, UART, SPI
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Operating Supply Voltage: 0.9 V to 3.6 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: C8051F930
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1472

C8051F93x-C8051F92x
SFR Definition 20.1. RTC0KEY: SmaRTClock Lock and Key
SFR Page = 0x0; SFR Address = 0xAE
200
Reset
Name
Type
7:0
Bit
Bit
RTC0ST
Name
7
0
SmaRTClock Interface Lock/Key and Status.
Locks/unlocks the SmaRTClock interface when written. Provides lock status when
read.
0
6
Read:
0x00: SmaRTClock Interface is locked.
0x01: SmaRTClock Interface is locked.
First key code (0xA5) has been written, waiting for second key code.
0x02: SmaRTClock Interface is unlocked.
First and second key codes (0xA5, 0xF1) have been written.
0x03: SmaRTClock Interface is disabled until the next system reset.
Write:
When RTC0ST = 0x00 (locked), writing 0xA5 followed by 0xF1 unlocks the
SmaRTClock Interface.
When RTC0ST = 0x01 (waiting for second key code), writing any value other
than the second key code (0xF1) will change RTC0STATE to 0x03 and disable
the SmaRTClock Interface until the next system reset.
When RTC0ST = 0x02 (unlocked), any write to RTC0KEY will lock the SmaRT-
Clock Interface.
When RTC0ST = 0x03 (disabled), writes to RTC0KEY have no effect.
5
0
Rev. 1.1
4
0
RTC0ST[7:0]
R/W
Function
3
0
2
0
1
0
0
0