SI1005-C-GM Silicon Laboratories Inc, SI1005-C-GM Datasheet - Page 363

• Manufacturer Part Number: SI1005-C-GM
• Description: IC TXRX MCU + EZRADIOPRO
• Manufacturer: Silicon Laboratories Inc

Specifications of SI1005-C-GM

• Package / Case: 42-QFN
• Frequency: 240MHz ~ 960MHz
• Data Rate - Maximum: 256kbps
• Modulation Or Protocol: FSK, GFSK, OOK
• Applications: General Purpose
• Power - Output: 13dBm
• Sensitivity: -121dBm
• Voltage - Supply: 0.9 V ~ 1.8 V
• Current - Receiving: 18.5mA
• Current - Transmitting: 30mA
• Data Interface: PCB, Surface Mount
• Memory Size: 32kB Flash, 4kB RAM
• Antenna Connector: PCB, Surface Mount
• Number Of Receivers: 1
• Number Of Transmitters: 1
• Wireless Frequency: 240 MHz to 960 MHz
• Interface Type: UART, SMBus, SPI, PCA
• Output Power: 13 dBm
• Operating Supply Voltage: 0.9 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Maximum Supply Current: 4.1 mA
• Minimum Operating Temperature: - 40 C
• Modulation: FSK, GFSK, OOK
• Protocol Supported: C2, SMBus
• Core: 8051
• Program Memory Type: Flash
• Program Memory Size: 32 KB
• Data Ram Size: 4352 B
• Supply Current (max): 4.1 mA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Operating Temperature: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1875-5

28.4. Watchdog Timer Mode
A programmable watchdog timer (WDT) function is available through the PCA Module 5. The WDT is used
to generate a reset if the time between writes to the WDT update register (PCA0CPH2) exceed a specified
limit. The WDT can be configured and enabled/disabled as needed by software.
With the WDTE bit set in the PCA0MD register, Module 5 operates as a watchdog timer (WDT). The Mod-
ule 5 high byte is compared to the PCA counter high byte; the Module 5 low byte holds the offset to be
used when WDT updates are performed. The Watchdog Timer is enabled on reset. Writes to some
PCA registers are restricted while the Watchdog Timer is enabled. The WDT will generate a reset
shortly after code begins execution. To avoid this reset, the WDT should be explicitly disabled (and option-
ally re-configured and re-enabled if it is used in the system).
28.4.1. Watchdog Timer Operation
While the WDT is enabled:






While the WDT is enabled, writes to the CR bit will not change the PCA counter state; the counter will run
until the WDT is disabled. The PCA counter run control bit (CR) will read zero if the WDT is enabled but
user software has not enabled the PCA counter. If a match occurs between PCA0CPH5 and PCA0H while
the WDT is enabled, a reset will be generated. To prevent a WDT reset, the WDT may be updated with a
write of any value to PCA0CPH5. Upon a PCA0CPH5 write, PCA0H plus the offset held in PCA0CPL5 is
loaded into PCA0CPH5 (See Figure 28.11).
Note that the 8-bit offset held in PCA0CPH5 is compared to the upper byte of the 16-bit PCA counter. This
offset value is the number of PCA0L overflows before a reset. Up to 256 PCA clocks may pass before the
first PCA0L overflow occurs, depending on the value of the PCA0L when the update is performed. The
total offset is then given (in PCA clocks) by Equation 28.5, where PCA0L is the value of the PCA0L register
at the time of the update.
PCA counter is forced on.
Writes to PCA0L and PCA0H are not allowed.
PCA clock source bits (CPS2 – CPS0) are frozen.
PCA Idle control bit (CIDL) is frozen.
Module 5 is forced into software timer mode.
Writes to the Module 5 mode register (PCA0CPM5) are disabled.
PCA0CPL5
C
D
L
I
W
D
T
E
PC A0M D
W
D
C
L
K
PCA 0C PH 2
C
P
S
2
Figure 28.11. PCA Module 5 with Watchdog Timer Enabled
W rite to
C
P
S
1
C
P
S
0
C
E
F
8-bit Adder
Enable
Adder
Enable
Rev. 1.0
PC A0C PH 5
C om parator
PC A 0H
8-bit
M atch
PCA0L O verflow
Si1000/1/2/3/4/5
R eset
363