 |
数据搜索系统，热门电子元器件搜索 |
|
|
数据搜索系统，热门电子元器件搜索 |
|
PIC18F258-E/SP 数据表(PDF) 75 Page - Microchip Technology |
|
|
|||||||||||||||||||||||||||||
PIC18F258-E/SP 数据表(HTML) 75 Page - Microchip Technology |
|
|
75 / 402 page  © 2006 Microchip Technology Inc. DS41159E-page 73 PIC18FXX8 EXAMPLE 6-3: WRITING TO FLASH PROGRAM MEMORY (CONTINUED) 6.5.2 WRITE VERIFY Depending on the application, good programming practice may dictate that the value written to the memory should be verified against the original value. This should be used in applications where excessive writes can stress bits near the specification limit. 6.5.3 UNEXPECTED TERMINATION OF WRITE OPERATION If a write is terminated by an unplanned event, such as loss of power or an unexpected Reset, the memory location just programmed should be verified and repro- grammed if needed.The WRERR bit is set when a write operation is interrupted by a MCLR Reset or a WDT Time-out Reset during normal operation. In these situations, users can check the WRERR bit and rewrite the location. 6.5.4 PROTECTION AGAINST SPURIOUS WRITES To reduce the probability against spurious writes to Flash program memory, the write initiate sequence must also be followed. See Section 24.0 “Special Features of the CPU” for more detail. 6.6 Flash Program Operation During Code Protection See Section 24.0 “Special Features of the CPU” for details on code protection of Flash program memory. WRITE_WORD_TO_HREGS MOVFW POSTINC0, W ; get low byte of buffer data MOVWF TABLAT ; present data to table latch TBLWT+* ; write data, perform a short write ; to internal TBLWT holding register. DECFSZ COUNTER ; loop until buffers are full BRA WRITE_WORD_TO_HREGS PROGRAM_MEMORY BSF EECON1, EEPGD ; point to FLASH program memory BCF EECON1, CFGS ; access FLASH program memory BSF EECON1, WREN ; enable write to memory BCF INTCON, GIE ; disable interrupts MOVLW 55h ; write 55h Required MOVWF EECON2 Sequence MOVLW 0AAh ; write 0AAh MOVWF EECON2 ; start program (CPU stall) BSF EECON1, WR NOP BSF INTCON, GIE ; re-enable interrupts DECFSZ COUNTER_HI ; loop until done BRA PROGRAM_LOOP BCF EECON1, WREN ; disable write to memory |
|
链接网址 |
| ALLDATASHEET是否为您带来帮助? [ DONATE ] |
关于 Alldatasheet | 广告服务 | 联系我们 | 隐私政策 | 数据表链接 | 链接交换 | 制造商名单 All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
Chinese ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
