C8051F326 Datasheet, PDF (66/140 Pages) List of Unclassifed Manufacturers – Full Speed USB, 16 kB Flash MCU Family

C8051F326/7
8.1.3. 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
8.1.2.
Step 3. Write the first key code to FLKEY: 0xA5.
Step 4. Write the second key code to FLKEY: 0xF1.
Step 5. Set the PSWE bit (register PSCTL).
Step 6. Clear the PSEE bit (register PSCTL).
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 (register PSCTL).
Steps 3-8 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 8.1. Flash Electrical Characteristics
Parameter
Conditions
Flash Size
C8051F326/7
Endurance
Erase Cycle Time
25 MHz System Clock
Write Cycle Time
25 MHz System Clock
*Note: 512 bytes at location 0x3E00 to 0x3FFF are reserved.
Min
16384*
20k
10
40
Typ
—
100k
15
55
Max
—
—
20
70
Units
bytes
Erase/Write
ms
µs
66
Rev. 0.5