C8051F330_07 Datasheet, PDF (106/216 Pages) Silicon Laboratories – Mixed Signal ISP Flash MCU Family

C8051F330/1/2/3/4/5
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
V_DD = 2.7 to 3.6 V; –40 to +85 ºC unless otherwise specified.
Parameter
Conditions
Min
Typ
Max
C8051F330/1
8192^*
—
—
Units
Flash Size
C8051F332/3
4096
—
—
bytes
Endurance
Erase Cycle Time
Write Cycle Time
C8051F334/5
25 MHz System Clock
25 MHz System Clock
2048
—
—
20 k 100 k
—
Erase/Write
10
15
20
ms
40
55
70
µs
*Note: 512 bytes at addresses 0x1E00 to 0x1FFF are reserved.
11.2. 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.
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Rev. 1.5