C8051F312-GQ Silicon Laboratories Inc, C8051F312-GQ Datasheet - Page 209

• Manufacturer Part Number: C8051F312-GQ
• Description: IC 8051 MCU 8K FLASH 32LQFP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F31xr

Specifications of C8051F312-GQ

• Program Memory Type: FLASH
• Program Memory Size: 8KB (8K x 8)
• Package / Case: 32-LQFP
• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 25MHz
• Connectivity: SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: POR, PWM, Temp Sensor, WDT
• Number Of I /o: 29
• Ram Size: 1.25K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 21x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: C8051F3x
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 1.25 KB
• Interface Type: I2C, SMBus, SPI, UART
• Maximum Clock Frequency: 25 MHz
• Number Of Programmable I/os: 29
• Number Of Timers: 4 bit
• Operating Supply Voltage: 2.7 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Development Tools By Supplier: C8051F310DK
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 21 Channel
• No. Of I/o's: 29
• Ram Memory Size: 1280Byte
• Cpu Speed: 25MHz
• No. Of Timers: 4
• Rohs Compliant: Yes
• Package: 32LQFP
• Device Core: 8051
• Family Name: C8051F31x
• Maximum Speed: 25 MHz
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 336-1445 - ADAPTER PROGRAM TOOLSTICK F310
• Eeprom Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1255

18.2.4. Frequency Output Mode
Frequency Output Mode produces a programmable-frequency square wave on the module’s associated
CEXn pin. The capture/compare module high byte holds the number of PCA clocks to count before the out-
put is toggled. The frequency of the square wave is then defined by Equation 18.1, where F
quency of the clock selected by the CPS2-0 bits in the PCA mode register, PCA0MD.
Note: A value of 0x00 in the PCA0CPHn register is equal to 256 for this equation.
The lower byte of the capture/compare module is compared to the PCA counter low byte; on a match,
CEXn is toggled and the offset held in the high byte is added to the matched value in PCA0CPLn. Fre-
quency Output Mode is enabled by setting the ECOMn, TOGn, and PWMn bits in the PCA0CPMn register.
PCA0CPLn
Write to
Reset
PCA0CPHn
Write to
0
1
ENB
ENB
Equation 18.1. Square Wave Frequency Output
Figure 18.7. PCA Frequency Output Mode
W
P
M
1
6
n
x
E
C
O
M
n
PCA0CPMn
C
A
P
P
n
0 0 0
C
N
A
P
n
M
A
T
n
O
G
T
n
W
P
M
n
C
C
E
F
n
x
PCA Timebase
F
CEXn
Enable
=
Comparator
PCA0CPLn
---------------------------------------- -
2
Rev. 1.7
PCA0L

8-bit
PCA0CPHn
F
C8051F310/1/2/3/4/5/6/7
PCA
match
Enable
Adder
8-bit Adder
Toggle
TOGn
0
1
CEXn
PCA0CPHn
Crossbar
PCA
is the fre-
Port I/O
209