C8051F321-GM Silicon Laboratories Inc, C8051F321-GM Datasheet - Page 118

• Manufacturer Part Number: C8051F321-GM
• Description: IC 8051 MCU 16K FLASH 28MLP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F32xr

Specifications of C8051F321-GM

• Program Memory Type: FLASH
• Program Memory Size: 16KB (16K x 8)
• Package / Case: 28-VQFN Exposed Pad, 28-HVQFN, 28-SQFN, 28-DHVQFN
• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 25MHz
• Connectivity: SMBus (2-Wire/I²C), SPI, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 21
• Ram Size: 2.25K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 13x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: C8051F3x
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 2.25 KB
• Interface Type: I2C/SMBus/SPI/UART/USB
• Maximum Clock Frequency: 25 MHz
• Number Of Programmable I/os: 21
• Number Of Timers: 4
• 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: C8051F320DK
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 13-ch x 10-bit or 17-ch x 10-bit
• No. Of I/o's: 21
• Ram Memory Size: 1280Byte
• Cpu Speed: 25MHz
• No. Of Timers: 4
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 336-1480 - DAUGHTER CARD TOOLSTCK C8051F321770-1006 - ISP 4PORT FOR SILABS C8051F MCU336-1449 - ADAPTER PROGRAM TOOLSTICK F321336-1260 - DEV KIT FOR C8051F320/F321
• Eeprom Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1261

C8051F320/1
Important Note: If the sum of the reset value of OSCICL and OSCICL is greater than 31 or less than 0,
then the device will not be capable of producing the desired frequency.
13.1.2. Internal Oscillator Suspend Mode
The internal oscillator may be placed in Suspend mode by writing ‘1’ to the SUSPEND bit in register
OSCICN. In Suspend mode, the internal oscillator is stopped until a non-idle USB event is detected (Sec-
tion 15) or VBUS matches the polarity selected by the VBPOL bit in register REG0CN (Section 8.2). The
transceiver is able to detect non-idle USB events even when it is placed in Suspend mode. On a non-idle
USB event, a Resume interrupt is generated, on receipt of which the PHYEN bit should be set to '1' to re-
enable the transceiver.
118
Note: The contents of this register are undefined when Clock Recovery is enabled. See Section “15.4. USB Clock
Bit7:
Bit6:
Bit5:
Bits4–2: UNUSED. Read = 000b, Write = don't care.
Bits1–0: IFCN1–0: Internal Oscillator Frequency Control Bits.
Bits7–5: Unused: Read = varies. Write = don’t care.
Bits4–0: OSCCAL: Oscillator Calibration Value
IOSCEN
R/W
R/W
Bit7
Bit7
-
Configuration” on page 146 for details on Clock Recovery.
IOSCEN: Internal Oscillator Enable Bit.
0: Internal Oscillator Disabled.
1: Internal Oscillator Enabled.
IFRDY: Internal Oscillator Frequency Ready Flag.
0: Internal Oscillator is not running at programmed frequency.
1: Internal Oscillator is running at programmed frequency.
SUSPEND: Force Suspend
Writing a ‘1’ to this bit will force the internal oscillator to be stopped. The oscillator will be re-
started on the next non-idle USB event (i.e., RESUME signaling) or VBUS interrupt event
(see Figure 8.1).
00: SYSCLK derived from Internal Oscillator divided by 8.
01: SYSCLK derived from Internal Oscillator divided by 4.
10: SYSCLK derived from Internal Oscillator divided by 2.
11: SYSCLK derived from Internal Oscillator divided by 1.
These bits determine the internal oscillator period as per Equation 13.1.
SFR Definition 13.2. OSCICL: Internal Oscillator Calibration
IFRDY
SFR Definition 13.1. OSCICN: Internal Oscillator Control
R/W
Bit6
Bit6
R
-
SUSPEND
R/W
R/W
Bit5
Bit5
-
R/W
Bit4
Bit4
R
-
Rev. 1.4
R/W
R/W
Bit3
Bit3
-
OSCCAL
R/W
Bit2
R/W
Bit2
-
IFCN1
R/W
Bit1
R/W
Bit1
IFCN0
R/W
Bit0
R/W
Bit0
SFR Address:
SFR Address:
10000000
Reset Value
Reset Value
Variable
0xB2
0xB3