;  RC4  vystup UART 
 ; tento program nic nevysila, i kdyz je udelan z uart02.asm
 ;   tento program slouzi na demonstraci prijimani znaku 
    
#include p16f1708.inc

    
 code 
 
  __CONFIG   _CONFIG1,  _FOSC_INTOSC & _WDTE_OFF & _PWRTE_ON  & _MCLRE_OFF & _CP_OFF & _BOREN_OFF  & _IESO_OFF &  _FCMEN_OFF & _CLKOUTEN_OFF 

;   & _CLKOUTEN_OFF   timhle se da vypnout vnitrni oscilator na pinu RA4 - pin 3 
    
  __CONFIG   _CONFIG2,  _WRT_OFF & _LVP_OFF   & _PPS1WAY_ON & _ZCDDIS_ON & _PLLEN_OFF & _STVREN_ON &  _LPBOR_OFF & _BORV_HI & _LPBOR_OFF  
  
  
  
  
PISMENKO:   equ  0x20  
PRIJATE:    equ  0x21
    
    
   org 0 
   goto start
   
   
   
   org 4
   
   banksel PIR1
 btfsc PIR2, TMR6IF 
 goto ODTMR6

 btfsc PIR2, TMR4IF 
 goto ODTMR4


 btfsc PIR1, TMR2IF 
 goto ODTMR2


 btfsc PIR1, RCIF 
 goto ODUARTURX  
 
 ;   btfsc PIR1, TXIF 
 ;   goto ODUARTUTX  
 
 ;  preruseni od vysilani mame zakazano  
 
 goto $
   
   
   
   
   
   
   
   
  start:
    
    ; oscilator  0 1101 x 1x nechci PLL, 4MHz oscil., x, vnitrni oscilator  
  ;   0110 1x1x   0x6a 

  banksel INTCON
  clrf INTCON

  banksel ADCON0
  movlw  0x6c       ; 0110 1100    11011 = Reserved. No channel connected.
  movwf ADCON0      ; vypinam prevodnik 


  banksel OSCCON
  movlw 0x6a     ; 0110 1010    -   1101 pro delicku  - 4MHz  
  movwf OSCCON 
  ; movlw 2E    ; 1F je maximalni frekvence 
              ;  2e je -18 , tedy o 1.6 procenta pomaleji 
  
  movlw 0      ; stredni frekvence  	      
  movwf OSCTUNE 
 
  banksel TRISA
  movlw 0xff
  movwf TRISA
  movwf TRISB
  movwf TRISC
  bcf TRISC,4   ;  tady bude vystup UATRu
  
  
  banksel ANSELA
  clrf ANSELA
  clrf ANSELB
  clrf ANSELC     ;  vsechny piny jsou digitalni  
  
  banksel PIE1
  clrf PIE1
  banksel PIE2
  clrf PIE2
  clrf PIE3  ;   stejna banka 
  
  

  
  
 ;  UNLOCK PPS 
 bcf INTCON,GIE  ; uspend interrupts
 BANKSEL PPSLOCK ; set bank
 ; required sequence, next 5 instructions
 movlw 0x55
 movwf PPSLOCK
 movlw 0xAA
 movwf PPSLOCK
 ; Set PPSLOCKED bit to disable writes or
 ; Clear PPSLOCKED bit to enable writes
 bcf PPSLOCK,PPSLOCKED
   
  
  ; RC4 bude vystup UARTu 
  banksel RC4PPS
  movlw   0x14    ;   10100 = Rxy source is TX/CK(1)
  movwf RC4PPS    ; stejna stranka jako RC3PPS

  ;RC5 bude vstup UARTu
  banksel RXPPS
  movlw 0x15
  movwf RXPPS
  
 BANKSEL PPSLOCK ; set bank
 ; required sequence, next 5 instructions
 movlw 0x55
 movwf PPSLOCK
 movlw 0xAA
 movwf PPSLOCK
 ; Set PPSLOCKED bit to disable writes or
 ; Clear PPSLOCKED bit to enable writes
 bsf PPSLOCK,PPSLOCKED
   ;   LOCK PPS 
  
  
  
  
  banksel TX1STA ;   vsechny ridici registry UARTu jsou ve stejne bance
  movlw 0x24    ;      TX1STA:   x010 0100   High speed   BRGH = 1 
  movwf TX1STA

  movlw 0x08     ; BAUD1CON: 0000 1000      data nejsou inverovana  16bit BRG
  movwf BAUD1CON  ;   BAud RATE je  FOSC/[4 (n+1)]      vychazi 416    tedy 0x1A0 

  movlw 0x10   ; RC1STA:   1001 0000      Enable receiver 
  movwf RC1STA   

  movlw 0x01
  movwf SP1BRGH
  movlw 0xa0
  movwf SP1BRGL

  bsf RC1STA,7  ; a tady to cele finalne zapinam 
  
  
    ;  nastavuji TMR6   
  ;  ma to tri TMR2, jmenuji se  2  4  6   
  ;  ???? ALE PWM umi jenom TMR2 nee, kterykoli TMR umi PWM !!!! 
  ;  POSTSCALLER 1:16   PRESCALLER 64   PR6 243   delime  249856
  ;  1MHZ :   249856   =   4Hz   
  ;  x 1111 1 11  =   x111 1111 = 0x7f   ; postscaller ON/OFF prescaller
  ; TMR6 vola preruseni 4x za 1 sec  

  banksel PR6   ; to je banka 8
  movlw .243
  movwf PR6
  movlw  0x7f ; 0x7f
  movwf T6CON    ;  zase vsechno stejna banka 8  

  banksel PIE2   ; jina banka - 1 
  bsf PIE2, TMR6IE   ;  poustim interrupt od TMR6

  banksel PISMENKO
  movlw 'A'
  movwf PISMENKO
  
    
    
    
      
  banksel PIE1
  bsf PIE1,RCIE  ;  povoluji preruseni od prijimace UARTu
  
  banksel 0 
  bsf INTCON, PEIE
  bsf INTCON,GIE  
    
    
cyklus:
    
    nop
    nop
    nop
    nop
    goto cyklus
    
   
    
ODTMR2:
    bcf PIR1, TMR2IF 
    retfie
    
    
    
ODTMR4:    
    bcf PIR2, TMR4IF 
    retfie
    
    
    
ODTMR6:    ;  sem skaceme 4x za 1 sec 
    bcf PIR2, TMR6IF 
        
    retfie
   
    
    
ODUARTUTX: 
    banksel PISMENKO
    movf PISMENKO,0
    incf PISMENKO
    banksel TX1REG
    movwf TX1REG
    
    banksel PISMENKO
    movlw 'Z' + 1
    subwf PISMENKO, 0         ;  bunka PISMENKO se nemeni !!!!!!! 
    btfss STATUS,Z 
    retfie
    
    movlw 'A'
    movwf PISMENKO
    banksel PIE1
    bcf PIE1,TXIE
    
    retfie
    
    
    
    
    
ODUARTURX:
    
    banksel RC1REG
    movf RC1REG,0
    banksel PRIJATE
    movwf PRIJATE
       ;  tohle je jen jednoduchy priklad na zpracovani prisedsiho znaku
       ;  tady dal pokracuje zpracovani prijateho cisla 
    retfie
    
    
    
    
    end