C8051F350 Silicon Laboratories Inc, C8051F350 Datasheet - Page 119

• Manufacturer Part Number: C8051F350
• Description: IC 8051 MCU 8K FLASH 32LQFP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F35xr

Specifications of C8051F350

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 50MHz
• Connectivity: SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: POR, PWM, Temp Sensor, WDT
• Number Of I /o: 17
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 768 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 8x24b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-LQFP
• Data Bus Width: 8 bit
• Data Rom Size: 128 B
• On-chip Adc: 10 bit
• Number Of Timers: 16 bit
• Operating Supply Voltage: 2.7 V to 3.6 V
• Mounting Style: SMD/SMT
• Height: 1.4 mm
• Length: 7 mm
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Width: 7 mm
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: No RoHS Version Available

15.2. Non-volatile Data Storage
The Flash memory can be used for non-volatile data storage as well as program code. This allows data
such as calibration coefficients to be calculated and stored at run time. Data is written using the MOVX
write instruction and read using the MOVC instruction. Note: MOVX read instructions always target XRAM.
15.3. Security Options
The CIP-51 provides security options to protect the Flash memory from inadvertent modification by soft-
ware as well as to prevent the viewing of proprietary program code and constants. The Program Store
Write Enable (bit PSWE in register PSCTL) and the Program Store Erase Enable (bit PSEE in register
PSCTL) bits protect the Flash memory from accidental modification by software. PSWE must be explicitly
set to ‘1’ before software can modify the Flash memory; both PSWE and PSEE must be set to ‘1’ before
software can erase Flash memory. Additional security features prevent proprietary program code and data
constants from being read or altered across the C2 interface.
A Security Lock Byte located at the last byte of Flash user space offers protection of the Flash program
memory from access (reads, writes, or erases) by unprotected code or the C2 interface. The Flash security
mechanism allows the user to lock n 512-byte Flash pages, starting at page 0 (addresses 0x0000 to
0x01FF), where n is the 1’s complement number represented by the Security Lock Byte. Note that the
page containing the Flash Security Lock Byte is locked when any other Flash pages are locked. See exam-
ple below.
Important Notes About the Flash Security:
Flash pages locked:
Security Lock Byte:
Addresses locked:
1’s Complement:
1. Clearing any bit of the Lock Byte to ‘0’ will lock the Flash page containing the Lock Byte (in
2. Locked pages cannot be read, written, or erased via the C2 interface.
3. Locked pages cannot be read, written, or erased by user firmware executing from unlocked
4. User firmware executing in a locked page may read and write Flash memory in any locked or
5. User firmware executing in a locked page may erase Flash memory in any locked or unlocked
6. Locked pages can only be unlocked by a C2 Device Erase command.
7. If a user firmware Flash access attempt is denied (per restrictions #3, #4, and #5 above), a
addition to the selected pages).
memory space.
unlocked page excluding the reserved area.
page excluding the reserved area and the page containing the Lock Byte.
Flash Error system reset will be generated.
0x0000 to 0x03FF (first two Flash pages) and
3 (First two Flash pages + Lock Byte Page)
0x1C00 to 0x1DFF (Lock Byte Page)
Rev. 0.4
00000010b
11111101b
C8051F350/1/2/3
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