diff options
Diffstat (limited to 'Source/portable/SDCC/PIC18/port.c')
| -rw-r--r-- | Source/portable/SDCC/PIC18/port.c | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/Source/portable/SDCC/PIC18/port.c b/Source/portable/SDCC/PIC18/port.c index 86c52bad..7bdf0fef 100644 --- a/Source/portable/SDCC/PIC18/port.c +++ b/Source/portable/SDCC/PIC18/port.c @@ -83,9 +83,9 @@ static void prvSetupTimerInterrupt(void); * When MR0ReloadValue=0 (65536 increments) configTICK_RATE_HZ=76Hz (with respect to values in FreeRTOSConfig.h) * When MR0ReloadValue=65535 (1 increment) configTICK_RATE_HZ=5MHz (with respect to values in FreeRTOSConfig.h) * This implies the bellow linear relation between configTICK_RATE_HZ and TMR0ReloadValue - * , if we accept that 1 is negligible with respect to 65535. + * TMR0ReloadValue=65536 - configCPU_CLOCK_HZ/(portTIMER_FOSC_SCALE*configTICK_RATE_HZ) */ -portSHORT TMR0ReloadValue=(portSHORT)(65536.0 -(float)(portTIMER_FOSC_SCALE*65536.0*configTICK_RATE_HZ/configCPU_CLOCK_HZ)+65537.0); +const unsigned portSHORT TMR0ReloadValue=(65536 - configCPU_CLOCK_HZ/(configTICK_RATE_HZ*portTIMER_FOSC_SCALE)); /* @@ -202,7 +202,7 @@ portBASE_TYPE xPortStartScheduler(void) /* Restore the context of the first task to run. */ portRESTORE_CONTEXT(); -
/* Should not get here. Use the function name to stop compiler warnings. */ + /* Should not get here. Use the function name to stop compiler warnings. */ ( void ) prvLowInterrupt; return pdTRUE; @@ -254,7 +254,11 @@ void vPortYield(void) __naked /* Interrupts must have been enabled for the ISR to fire, so we have to save the context with interrupts enabled. */ portSAVE_CONTEXT(portGLOBAL_INTERRUPT_FLAG); + INTCONbits.TMR0IF=0; + /*set TMR0L and TMR0H vlaue*/ + TMR0H=(unsigned portCHAR)((TMR0ReloadValue&(unsigned portSHORT)0xff00)>>8); + TMR0L=(unsigned portCHAR)(TMR0ReloadValue&(unsigned portSHORT)0x00ff); /* Maintain the tick count. */ vTaskIncrementTick(); @@ -283,15 +287,13 @@ static void prvSetupTimerInterrupt(void) INTCONbits.TMR0IF=0; /*Timer0 interrupt flag cleared*/ INTCON2bits.T0IP=0; /*TimerO has low priority interrupt*/ - /**/ - TMR0H=0x00; /*Initialize timer0 high byte register*/ - TMR0L=0x00; /*Initialize timer0 low byte register*/ - + /*set TMR0L and TMR0H vlaue*/ + TMR0H=(unsigned portCHAR)((TMR0ReloadValue&(unsigned portSHORT)0xff00)>>8); + TMR0L=(unsigned portCHAR)(TMR0ReloadValue&(unsigned portSHORT)0x00ff); RCONbits.IPEN=1; /* Interrupt priority feature enabled. FIXME: this is * something like hardware interrupt controller configu- * ration, so needs to be done somewhere else I think */ - T0CONbits.TMR0ON=1; /*Now enable timer0*/ } |