diff options
Diffstat (limited to 'portable/BCC/16BitDOS/PC/port.c')
| -rw-r--r-- | portable/BCC/16BitDOS/PC/port.c | 121 |
1 files changed, 57 insertions, 64 deletions
diff --git a/portable/BCC/16BitDOS/PC/port.c b/portable/BCC/16BitDOS/PC/port.c index e8a14a881..6940b1a67 100644 --- a/portable/BCC/16BitDOS/PC/port.c +++ b/portable/BCC/16BitDOS/PC/port.c @@ -27,16 +27,16 @@ */ /* - * Changes from V2.6.1 - * - + Replaced the sUsingPreemption variable with the configUSE_PREEMPTION - + macro to be consistent with the later ports. - + - + Changes from V4.0.1 - + - + Add function prvSetTickFrequencyDefault() to set the DOS tick back to - + its proper value when the scheduler exits. - */ +Changes from V2.6.1 + + + Replaced the sUsingPreemption variable with the configUSE_PREEMPTION + macro to be consistent with the later ports. + +Changes from V4.0.1 + + + Add function prvSetTickFrequencyDefault() to set the DOS tick back to + its proper value when the scheduler exits. +*/ #include <stdlib.h> #include <dos.h> @@ -47,9 +47,9 @@ #include "portasm.h" /*----------------------------------------------------------- -* Implementation of functions defined in portable.h for the industrial -* PC port. -*----------------------------------------------------------*/ + * Implementation of functions defined in portable.h for the industrial + * PC port. + *----------------------------------------------------------*/ /*lint -e950 Non ANSI reserved words okay in this file only. */ @@ -62,21 +62,19 @@ static void prvSetTickFrequency( uint32_t ulTickRateHz ); static void prvExitFunction( void ); /* Either chain to the DOS tick (which itself clears the PIC) or clear the PIC - * directly. We chain to the DOS tick as close as possible to the standard DOS - * tick rate. */ +directly. We chain to the DOS tick as close as possible to the standard DOS +tick rate. */ static void prvPortResetPIC( void ); /* The ISR used depends on whether the preemptive or cooperative - * scheduler is being used. */ -#if ( configUSE_PREEMPTION == 1 ) - -/* Tick service routine used by the scheduler when preemptive scheduling is - * being used. */ +scheduler is being used. */ +#if( configUSE_PREEMPTION == 1 ) + /* Tick service routine used by the scheduler when preemptive scheduling is + being used. */ static void __interrupt __far prvPreemptiveTick( void ); #else - -/* Tick service routine used by the scheduler when cooperative scheduling is - * being used. */ + /* Tick service routine used by the scheduler when cooperative scheduling is + being used. */ static void __interrupt __far prvNonPreemptiveTick( void ); #endif @@ -84,7 +82,7 @@ static void prvPortResetPIC( void ); static void __interrupt __far prvYieldProcessor( void ); /* Set the tick frequency back so the floppy drive works correctly when the - * scheduler exits. */ +scheduler exits. */ static void prvSetTickFrequencyDefault( void ); /*lint -e956 File scopes necessary here. */ @@ -96,10 +94,10 @@ static int16_t sDOSTickCounter; static BaseType_t xSchedulerRunning = pdFALSE; /* Points to the original routine installed on the vector we use for manual context switches. This is then used to restore the original routine during prvExitFunction(). */ -static void( __interrupt __far * pxOldSwitchISR )(); +static void ( __interrupt __far *pxOldSwitchISR )(); /* Points to the original routine installed on the vector we use to chain to the DOS tick. This is then used to restore the original routine during prvExitFunction(). */ -static void( __interrupt __far * pxOldSwitchISRPlus1 )(); +static void ( __interrupt __far *pxOldSwitchISRPlus1 )(); /* Used to restore the original DOS context when the scheduler is ended. */ static jmp_buf xJumpBuf; @@ -109,12 +107,12 @@ static jmp_buf xJumpBuf; /*-----------------------------------------------------------*/ BaseType_t xPortStartScheduler( void ) { - pxISR pxOriginalTickISR; +pxISR pxOriginalTickISR; /* This is called with interrupts already disabled. */ /* Remember what was on the interrupts we are going to use - * so we can put them back later if required. */ + so we can put them back later if required. */ pxOldSwitchISR = _dos_getvect( portSWITCH_INT_NUMBER ); pxOriginalTickISR = _dos_getvect( portTIMER_INT_NUMBER ); pxOldSwitchISRPlus1 = _dos_getvect( portSWITCH_INT_NUMBER + 1 ); @@ -122,16 +120,16 @@ BaseType_t xPortStartScheduler( void ) prvSetTickFrequency( configTICK_RATE_HZ ); /* Put our manual switch (yield) function on a known - * vector. */ + vector. */ _dos_setvect( portSWITCH_INT_NUMBER, prvYieldProcessor ); /* Put the old tick on a different interrupt number so we can - * call it when we want. */ + call it when we want. */ _dos_setvect( portSWITCH_INT_NUMBER + 1, pxOriginalTickISR ); /* The ISR used depends on whether the preemptive or cooperative - * scheduler is being used. */ - #if ( configUSE_PREEMPTION == 1 ) + scheduler is being used. */ + #if( configUSE_PREEMPTION == 1 ) { /* Put our tick switch function on the timer interrupt. */ _dos_setvect( portTIMER_INT_NUMBER, prvPreemptiveTick ); @@ -144,8 +142,8 @@ BaseType_t xPortStartScheduler( void ) #endif /* Setup a counter that is used to call the DOS interrupt as close - * to it's original frequency as can be achieved given our chosen tick - * frequency. */ + to it's original frequency as can be achieved given our chosen tick + frequency. */ sDOSTickCounter = portTICKS_PER_DOS_TICK; /* Clean up function if we want to return to DOS. */ @@ -167,8 +165,8 @@ BaseType_t xPortStartScheduler( void ) /*-----------------------------------------------------------*/ /* The ISR used depends on whether the preemptive or cooperative - * scheduler is being used. */ -#if ( configUSE_PREEMPTION == 1 ) +scheduler is being used. */ +#if( configUSE_PREEMPTION == 1 ) static void __interrupt __far prvPreemptiveTick( void ) { /* Get the scheduler to update the task states following the tick. */ @@ -181,15 +179,15 @@ BaseType_t xPortStartScheduler( void ) /* Reset the PIC ready for the next time. */ prvPortResetPIC(); } -#else /* if ( configUSE_PREEMPTION == 1 ) */ +#else static void __interrupt __far prvNonPreemptiveTick( void ) { /* Same as preemptive tick, but the cooperative scheduler is being used - * so we don't have to switch in the context of the next task. */ + so we don't have to switch in the context of the next task. */ xTaskIncrementTick(); prvPortResetPIC(); } -#endif /* if ( configUSE_PREEMPTION == 1 ) */ +#endif /*-----------------------------------------------------------*/ static void __interrupt __far prvYieldProcessor( void ) @@ -202,22 +200,19 @@ static void __interrupt __far prvYieldProcessor( void ) static void prvPortResetPIC( void ) { /* We are going to call the DOS tick interrupt at as close a - * frequency to the normal DOS tick as possible. */ + frequency to the normal DOS tick as possible. */ /* WE SHOULD NOT DO THIS IF YIELD WAS CALLED. */ --sDOSTickCounter; - if( sDOSTickCounter <= 0 ) { sDOSTickCounter = ( int16_t ) portTICKS_PER_DOS_TICK; - __asm { - int portSWITCH_INT_NUMBER + 1 - }; + __asm{ int portSWITCH_INT_NUMBER + 1 }; } else { /* Reset the PIC as the DOS tick is not being called to - * do it. */ + do it. */ __asm { mov al, 20H @@ -230,20 +225,19 @@ static void prvPortResetPIC( void ) void vPortEndScheduler( void ) { /* Jump back to the processor state prior to starting the - * scheduler. This means we are not going to be using a - * task stack frame so the task can be deleted. */ + scheduler. This means we are not going to be using a + task stack frame so the task can be deleted. */ longjmp( xJumpBuf, 1 ); } /*-----------------------------------------------------------*/ static void prvExitFunction( void ) { - void( __interrupt __far * pxOriginalTickISR )(); +void ( __interrupt __far *pxOriginalTickISR )(); /* Interrupts should be disabled here anyway - but no - * harm in making sure. */ + harm in making sure. */ portDISABLE_INTERRUPTS(); - if( xSchedulerRunning == pdTRUE ) { /* Set the DOS tick back onto the timer ticker. */ @@ -252,29 +246,28 @@ static void prvExitFunction( void ) prvSetTickFrequencyDefault(); /* Put back the switch interrupt routines that was in place - * before the scheduler started. */ + before the scheduler started. */ _dos_setvect( portSWITCH_INT_NUMBER, pxOldSwitchISR ); _dos_setvect( portSWITCH_INT_NUMBER + 1, pxOldSwitchISRPlus1 ); } - /* The tick timer is back how DOS wants it. We can re-enable - * interrupts without the scheduler being called. */ + interrupts without the scheduler being called. */ portENABLE_INTERRUPTS(); } /*-----------------------------------------------------------*/ static void prvSetTickFrequency( uint32_t ulTickRateHz ) { - const uint16_t usPIT_MODE = ( uint16_t ) 0x43; - const uint16_t usPIT0 = ( uint16_t ) 0x40; - const uint32_t ulPIT_CONST = ( uint32_t ) 1193180UL; - const uint16_t us8254_CTR0_MODE3 = ( uint16_t ) 0x36; - uint32_t ulOutput; +const uint16_t usPIT_MODE = ( uint16_t ) 0x43; +const uint16_t usPIT0 = ( uint16_t ) 0x40; +const uint32_t ulPIT_CONST = ( uint32_t ) 1193180UL; +const uint16_t us8254_CTR0_MODE3 = ( uint16_t ) 0x36; +uint32_t ulOutput; /* Setup the 8245 to tick at the wanted frequency. */ portOUTPUT_BYTE( usPIT_MODE, us8254_CTR0_MODE3 ); ulOutput = ulPIT_CONST / ulTickRateHz; - portOUTPUT_BYTE( usPIT0, ( uint16_t ) ( ulOutput & ( uint32_t ) 0xff ) ); + portOUTPUT_BYTE( usPIT0, ( uint16_t )( ulOutput & ( uint32_t ) 0xff ) ); ulOutput >>= 8; portOUTPUT_BYTE( usPIT0, ( uint16_t ) ( ulOutput & ( uint32_t ) 0xff ) ); } @@ -282,13 +275,13 @@ static void prvSetTickFrequency( uint32_t ulTickRateHz ) static void prvSetTickFrequencyDefault( void ) { - const uint16_t usPIT_MODE = ( uint16_t ) 0x43; - const uint16_t usPIT0 = ( uint16_t ) 0x40; - const uint16_t us8254_CTR0_MODE3 = ( uint16_t ) 0x36; +const uint16_t usPIT_MODE = ( uint16_t ) 0x43; +const uint16_t usPIT0 = ( uint16_t ) 0x40; +const uint16_t us8254_CTR0_MODE3 = ( uint16_t ) 0x36; portOUTPUT_BYTE( usPIT_MODE, us8254_CTR0_MODE3 ); - portOUTPUT_BYTE( usPIT0, 0 ); - portOUTPUT_BYTE( usPIT0, 0 ); + portOUTPUT_BYTE( usPIT0,0 ); + portOUTPUT_BYTE( usPIT0,0 ); } |