C8051F321-GM Silicon Laboratories Inc, C8051F321-GM Datasheet - Page 111

• 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

11.4.2. 16.4.2 PSWE Maintenance
11.4.3. System Clock
7. Reduce the number of places in code where the PSWE bit (b0 in PSCTL) is set to a '1'. There
8. Minimize the number of variable accesses while PSWE is set to a '1'. Handle pointer address
9. Disable interrupts prior to setting PSWE to a '1' and leave them disabled until after PSWE has
10. Make certain that the Flash write and erase pointer variables are not located in XRAM. See
11. Add address bounds checking to the routines that write or erase Flash memory to ensure that
12. If operating from an external crystal, be advised that crystal performance is susceptible to
13. If operating from the external oscillator, switch to the internal oscillator during Flash write or
should be exactly one routine in code that sets PSWE to a '1' to write Flash bytes and one rou-
tine in code that sets both PSWE and PSEE both to a '1' to erase Flash pages.
updates and loop maintenance outside the "PSWE = 1; ... PSWE = 0;" area. Code examples
showing this can be found in AN201, "Writing to Flash from Firmware", available from the Sili-
con Laboratories web site.
been reset to '0'. Any interrupts posted during the Flash write or erase operation will be ser-
viced in priority order after the Flash operation has been completed and interrupts have been
re-enabled by software.
your compiler documentation for instructions regarding how to explicitly locate variables in dif-
ferent memory areas.
a routine called with an illegal address does not result in modification of the Flash.
electrical interference and is sensitive to layout and to changes in temperature. If the system is
operating in an electrically noisy environment, use the internal oscillator or use an external
CMOS clock.
erase operations. The external oscillator can continue to run, and the CPU can switch back to
the external oscillator after the Flash operation has completed.
Rev. 1.4
C8051F320/1
111