TOOLSTICK542PP Silicon Laboratories Inc, TOOLSTICK542PP Datasheet - Page 119

• Manufacturer Part Number: TOOLSTICK542PP
• Description: PLATFORM PROG TOOLSTICK F542
• Manufacturer: Silicon Laboratories Inc
• Series: ToolStickr
• Type: Microcontroller Programmerr

Specifications of TOOLSTICK542PP

• Contents: 2 Boards and USB Connecting Cable
• Processor To Be Evaluated: C8051F542
• Interface Type: USB
• Operating Supply Voltage: 2.7 V to 3.6 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: C8051F542
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1718

14.2. 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.
14.3. 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 soft-
ware 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 ones complement number represented by the Security Lock Byte. Note that the
page containing the Flash Security Lock Byte is unlocked when no other Flash pages are locked
(all bits of the Lock Byte are 1) and locked when any other Flash pages are locked (any bit of the
Lock Byte is 0). See example in Figure 14.1.
Security Lock Byte:
1s Complement:
Flash pages locked:
any other FLASH
pages are locked
according to the
Access limit set
FLASH security
Locked when
lock byte
11111101b
00000010b
3 (First two Flash pages + Lock Byte Page)
Figure 14.1. Flash Program Memory Map
Rev. 1.1
Unlocked FLASH Pages
Locked Flash Pages
Lock Byte Page
Reserved Area
Lock Byte
C8051F54x
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