iAmqq

AN1310

High-Speed Serial Bootloader for PIC16 and PIC18 Devices

 

使用此範例時, 若clock source為INT RC ,需注意Internal Oscillator Frequency Select bits的設定.在程式中除非define USE_MAX_INTOSC,才會更改OSCCON,否則將以default INT RC來執行,

 

以PIC16F1937為例, default為500kHz, 應該是太慢,PC端會連不上 device(bootloader not found),

若不開啟USE_MAX_INTOSC, 可在程式中加入紅色code

 

#ifdef USE_MAX_INTOSC

   banksel OSCCON                  ; Bx -> B1

   #ifdef USE_PLL                  

   movlw   b'11110000'             ; switch to 8MHz internal oscillator with PLL (32MHz)

   movwf   OSCCON

   #else

   movlw   b'01111000'             ; switch to 16MHz internal oscillator without PLL

   movwf   OSCCON

   #endif

;;add by iamqq

#else

   banksel OSCCON                ; Bx -> B1

   movlw   b'01100000'             ; switch internal oscillator without PLL (PS:at least 2Mhz)

   movwf   OSCCON

;;end add

#endif

 

而若要Manual Break and Reset for Re-Entry,

1. 按PCui 上的暫停鍵(Break/Reset App F/W)

2.按版子的MCLR key to reset

3. 按PCui 上的停止鍵(Bootloader mode)