Specifications

C8051F330/1
98 Rev. 1.1
11.1.3. FLASH Write Procedure
FLASH bytes are programmed by software with the following sequence:
Step 1. Disable interrupts (recommended).
Step 2. Erase the 512-byte FLASH page containing the target location, as described in Section 11.1.2.
Step 3. Set the PSWE bit (register PSCTL).
Step 4. Clear the PSEE bit (register PSCTL).
Step 5. Write the first key code to FLKEY: 0xA5.
Step 6. Write the second key code to FLKEY: 0xF1.
Step 7. Using the MOVX instruction, write a single data byte to the desired location within the 512-byte
sector.
Step 8. Clear the PSWE bit.
Steps 5-7 must be repeated for each byte to be written. After FLASH writes are complete, PSWE should be cleared so
that MOVX instructions do not target program memory.
Table 11.1. FLASH Electrical Characteristics
VDD = 2.7 to 3.6V; -40 to +85 ºC unless otherwise specified
PARAMETER CONDITIONS MIN TYP MAX UNITS
FLASH Size C8051F330/1
8192
†
bytes
Endurance 20k 100k Erase/Write
Erase Cycle Time 25 MHz System Clock 10 15 20 ms
Write Cycle Time 25 MHz System Clock 40 55 70 µs
†
Note: 512 bytes at addresses 0x1E00 to 0x1FFF are reserved.