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MW22-02A/OS2/uC-CPU/ARM-Cortex-M4/cpu_c.c

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汇源原始工程
2025-05-21 01:55:40 +00:00
/*
*********************************************************************************************************
* uC/CPU
* CPU CONFIGURATION & PORT LAYER
*
* (c) Copyright 2004-2011; Micrium, Inc.; Weston, FL
*
* All rights reserved. Protected by international copyright laws.
*
* uC/CPU is provided in source form to registered licensees ONLY. It is
* illegal to distribute this source code to any third party unless you receive
* written permission by an authorized Micrium representative. Knowledge of
* the source code may NOT be used to develop a similar product.
*
* Please help us continue to provide the Embedded community with the finest
* software available. Your honesty is greatly appreciated.
*
* You can contact us at www.micrium.com.
*********************************************************************************************************
*/
/*
*********************************************************************************************************
*
* CPU PORT FILE
*
* ARM-Cortex-M4
* IAR C Compiler
*
* Filename : cpu_c.c
* Version : V1.29.01.00
* Programmer(s) : JJL
* BAN
*********************************************************************************************************
*/
/*
*********************************************************************************************************
* INCLUDE FILES
*********************************************************************************************************
*/
#define MICRIUM_SOURCE
#include <cpu.h>
#include <cpu_core.h>
#include <lib_def.h>
/*$PAGE*/
/*
*********************************************************************************************************
* LOCAL DEFINES
*********************************************************************************************************
*/
#define CPU_INT_SRC_POS_MAX ((((CPU_REG_NVIC_NVIC + 1) & 0x1F) * 32) + 16)
#define CPU_BIT_BAND_SRAM_REG_LO 0x20000000
#define CPU_BIT_BAND_SRAM_REG_HI 0x200FFFFF
#define CPU_BIT_BAND_SRAM_BASE 0x22000000
#define CPU_BIT_BAND_PERIPH_REG_LO 0x40000000
#define CPU_BIT_BAND_PERIPH_REG_HI 0x400FFFFF
#define CPU_BIT_BAND_PERIPH_BASE 0x42000000
/*
*********************************************************************************************************
* LOCAL CONSTANTS
*********************************************************************************************************
*/
/*
*********************************************************************************************************
* LOCAL DATA TYPES
*********************************************************************************************************
*/
/*
*********************************************************************************************************
* LOCAL TABLES
*********************************************************************************************************
*/
/*
*********************************************************************************************************
* LOCAL GLOBAL VARIABLES
*********************************************************************************************************
*/
/*
*********************************************************************************************************
* LOCAL FUNCTION PROTOTYPES
*********************************************************************************************************
*/
/*
*********************************************************************************************************
* LOCAL CONFIGURATION ERRORS
*********************************************************************************************************
*/
/*$PAGE*/
/*
*********************************************************************************************************
* CPU_BitBandClr()
*
* Description : Clear bit in bit-band region.
*
* Argument(s) : addr Byte address in memory space.
*
* bit_nbr Bit number in byte.
*
* Return(s) : none.
*
* Caller(s) : Application.
*
* Note(s) : none.
*********************************************************************************************************
*/
void CPU_BitBandClr (CPU_ADDR addr,
CPU_INT08U bit_nbr)
{
CPU_ADDR bit_word_off;
CPU_ADDR bit_word_addr;
if ((addr >= CPU_BIT_BAND_SRAM_REG_LO) &&
(addr <= CPU_BIT_BAND_SRAM_REG_HI)) {
bit_word_off = ((addr - CPU_BIT_BAND_SRAM_REG_LO ) * 32) + (bit_nbr * 4);
bit_word_addr = CPU_BIT_BAND_SRAM_BASE + bit_word_off;
*(volatile CPU_INT32U *)(bit_word_addr) = 0;
} else if ((addr >= CPU_BIT_BAND_PERIPH_REG_LO) &&
(addr <= CPU_BIT_BAND_PERIPH_REG_HI)) {
bit_word_off = ((addr - CPU_BIT_BAND_PERIPH_REG_LO) * 32) + (bit_nbr * 4);
bit_word_addr = CPU_BIT_BAND_PERIPH_BASE + bit_word_off;
*(volatile CPU_INT32U *)(bit_word_addr) = 0;
}
}
/*$PAGE*/
/*
*********************************************************************************************************
* CPU_BitBandSet()
*
* Description : Set bit in bit-band region.
*
* Argument(s) : addr Byte address in memory space.
*
* bit_nbr Bit number in byte.
*
* Return(s) : none.
*
* Caller(s) : Application.
*
* Note(s) : none.
*********************************************************************************************************
*/
void CPU_BitBandSet (CPU_ADDR addr,
CPU_INT08U bit_nbr)
{
CPU_ADDR bit_word_off;
CPU_ADDR bit_word_addr;
if ((addr >= CPU_BIT_BAND_SRAM_REG_LO) &&
(addr <= CPU_BIT_BAND_SRAM_REG_HI)) {
bit_word_off = ((addr - CPU_BIT_BAND_SRAM_REG_LO ) * 32) + (bit_nbr * 4);
bit_word_addr = CPU_BIT_BAND_SRAM_BASE + bit_word_off;
*(volatile CPU_INT32U *)(bit_word_addr) = 1;
} else if ((addr >= CPU_BIT_BAND_PERIPH_REG_LO) &&
(addr <= CPU_BIT_BAND_PERIPH_REG_HI)) {
bit_word_off = ((addr - CPU_BIT_BAND_PERIPH_REG_LO) * 32) + (bit_nbr * 4);
bit_word_addr = CPU_BIT_BAND_PERIPH_BASE + bit_word_off;
*(volatile CPU_INT32U *)(bit_word_addr) = 1;
}
}
/*$PAGE*/
/*
*********************************************************************************************************
* CPU_IntSrcDis()
*
* Description : Disable an interrupt source.
*
* Argument(s) : pos Position of interrupt vector in interrupt table :
*
* 0 Invalid (see Note #1a).
* 1 Invalid (see Note #1b).
* 2 Non-maskable interrupt.
* 3 Hard Fault.
* 4 Memory Management.
* 5 Bus Fault.
* 6 Usage Fault.
* 7-10 Reserved.
* 11 SVCall
* 12 Debug monitor.
* 13 Reserved
* 14 PendSV.
* 15 SysTick.
* 16+ External Interrupt.
*
* Return(s) : none.
*
* Caller(s) : Application.
*
* Note(s) : (1) Several table positions do not contain interrupt sources :
*
* (a) Position 0 contains the stack pointer.
* (b) Positions 7-10, 13 are reserved.
*
* (2) Several interrupts cannot be disabled/enabled :
*
* (a) Reset.
* (b) NMI.
* (c) Hard fault.
* (d) SVCall.
* (e) Debug monitor.
* (f) PendSV.
*
* (3) The maximum Cortex-M3 table position is 256. A particular Cortex-M3 may have fewer
* than 240 external exceptions and, consequently, fewer than 256 table positions.
* This function assumes that the specified table position is valid if the interrupt
* controller type register's INTLINESNUM field is large enough so that the position
* COULD be valid.
*********************************************************************************************************
*/
/*$PAGE*/
void CPU_IntSrcDis (CPU_INT08U pos)
{
CPU_INT08U group;
CPU_INT08U pos_max;
CPU_INT08U nbr;
CPU_SR_ALLOC();
switch (pos) {
case CPU_INT_STK_PTR: /* ---------------- INVALID OR RESERVED --------------- */
case CPU_INT_RSVD_07:
case CPU_INT_RSVD_08:
case CPU_INT_RSVD_09:
case CPU_INT_RSVD_10:
case CPU_INT_RSVD_13:
break;
/* ----------------- SYSTEM EXCEPTIONS ---------------- */
case CPU_INT_RESET: /* Reset (see Note #2). */
case CPU_INT_NMI: /* Non-maskable interrupt (see Note #2). */
case CPU_INT_HFAULT: /* Hard fault (see Note #2). */
case CPU_INT_SVCALL: /* SVCall (see Note #2). */
case CPU_INT_DBGMON: /* Debug monitor (see Note #2). */
case CPU_INT_PENDSV: /* PendSV (see Note #2). */
break;
case CPU_INT_MEM: /* Memory management. */
CPU_CRITICAL_ENTER();
CPU_REG_NVIC_SHCSR &= ~CPU_REG_NVIC_SHCSR_MEMFAULTENA;
CPU_CRITICAL_EXIT();
break;
case CPU_INT_BUSFAULT: /* Bus fault. */
CPU_CRITICAL_ENTER();
CPU_REG_NVIC_SHCSR &= ~CPU_REG_NVIC_SHCSR_BUSFAULTENA;
CPU_CRITICAL_EXIT();
break;
case CPU_INT_USAGEFAULT: /* Usage fault. */
CPU_CRITICAL_ENTER();
CPU_REG_NVIC_SHCSR &= ~CPU_REG_NVIC_SHCSR_USGFAULTENA;
CPU_CRITICAL_EXIT();
break;
case CPU_INT_SYSTICK: /* SysTick. */
CPU_CRITICAL_ENTER();
CPU_REG_NVIC_ST_CTRL &= ~CPU_REG_NVIC_ST_CTRL_ENABLE;
CPU_CRITICAL_EXIT();
break;
/* ---------------- EXTERNAL INTERRUPT ---------------- */
default:
pos_max = CPU_INT_SRC_POS_MAX;
if (pos < pos_max) { /* See Note #3. */
group = (pos - 16) / 32;
nbr = (pos - 16) % 32;
CPU_CRITICAL_ENTER();
CPU_REG_NVIC_CLREN(group) = DEF_BIT(nbr);
CPU_CRITICAL_EXIT();
}
break;
}
}
/*$PAGE*/
/*
*********************************************************************************************************
* CPU_IntSrcEn()
*
* Description : Enable an interrupt source.
*
* Argument(s) : pos Position of interrupt vector in interrupt table (see 'CPU_IntSrcDis()').
*
* Return(s) : none.
*
* Caller(s) : Application.
*
* Note(s) : (1) See 'CPU_IntSrcDis() Note #1'.
*
* (2) See 'CPU_IntSrcDis() Note #2'.
*
* (3) See 'CPU_IntSrcDis() Note #3'.
*********************************************************************************************************
*/
void CPU_IntSrcEn (CPU_INT08U pos)
{
CPU_INT08U group;
CPU_INT08U nbr;
CPU_INT08U pos_max;
CPU_SR_ALLOC();
switch (pos) {
case CPU_INT_STK_PTR: /* ---------------- INVALID OR RESERVED --------------- */
case CPU_INT_RSVD_07:
case CPU_INT_RSVD_08:
case CPU_INT_RSVD_09:
case CPU_INT_RSVD_10:
case CPU_INT_RSVD_13:
break;
/* ----------------- SYSTEM EXCEPTIONS ---------------- */
case CPU_INT_RESET: /* Reset (see Note #2). */
case CPU_INT_NMI: /* Non-maskable interrupt (see Note #2). */
case CPU_INT_HFAULT: /* Hard fault (see Note #2). */
case CPU_INT_SVCALL: /* SVCall (see Note #2). */
case CPU_INT_DBGMON: /* Debug monitor (see Note #2). */
case CPU_INT_PENDSV: /* PendSV (see Note #2). */
break;
case CPU_INT_MEM: /* Memory management. */
CPU_CRITICAL_ENTER();
CPU_REG_NVIC_SHCSR |= CPU_REG_NVIC_SHCSR_MEMFAULTENA;
CPU_CRITICAL_EXIT();
break;
case CPU_INT_BUSFAULT: /* Bus fault. */
CPU_CRITICAL_ENTER();
CPU_REG_NVIC_SHCSR |= CPU_REG_NVIC_SHCSR_BUSFAULTENA;
CPU_CRITICAL_EXIT();
break;
case CPU_INT_USAGEFAULT: /* Usage fault. */
CPU_CRITICAL_ENTER();
CPU_REG_NVIC_SHCSR |= CPU_REG_NVIC_SHCSR_USGFAULTENA;
CPU_CRITICAL_EXIT();
break;
case CPU_INT_SYSTICK: /* SysTick. */
CPU_CRITICAL_ENTER();
CPU_REG_NVIC_ST_CTRL |= CPU_REG_NVIC_ST_CTRL_ENABLE;
CPU_CRITICAL_EXIT();
break;
/* ---------------- EXTERNAL INTERRUPT ---------------- */
default:
pos_max = CPU_INT_SRC_POS_MAX;
if (pos < pos_max) { /* See Note #3. */
group = (pos - 16) / 32;
nbr = (pos - 16) % 32;
CPU_CRITICAL_ENTER();
CPU_REG_NVIC_SETEN(group) = DEF_BIT(nbr);
CPU_CRITICAL_EXIT();
}
break;
}
}
/*$PAGE*/
/*
*********************************************************************************************************
* CPU_IntSrcPendClr()
*
* Description : Clear a pending interrupt.
*
* Argument(s) : pos Position of interrupt vector in interrupt table (see 'CPU_IntSrcDis()').
*
* Return(s) : none.
*
* Caller(s) : Application.
*
* Note(s) : (1) See 'CPU_IntSrcDis() Note #1'.
*
* (2) The pending status of several interrupts cannot be clear/set :
*
* (a) Reset.
* (b) NMI.
* (c) Hard fault.
* (d) Memory Managment.
* (e) Bus Fault.
* (f) Usage Fault.
* (g) SVCall.
* (h) Debug monitor.
* (i) PendSV.
* (j) Systick
*
* (3) See 'CPU_IntSrcDis() Note #3'.
*********************************************************************************************************
*/
void CPU_IntSrcPendClr (CPU_INT08U pos)
{
CPU_INT08U group;
CPU_INT08U nbr;
CPU_INT08U pos_max;
CPU_SR_ALLOC();
switch (pos) {
case CPU_INT_STK_PTR: /* ---------------- INVALID OR RESERVED --------------- */
case CPU_INT_RSVD_07:
case CPU_INT_RSVD_08:
case CPU_INT_RSVD_09:
case CPU_INT_RSVD_10:
case CPU_INT_RSVD_13:
break;
/* ----------------- SYSTEM EXCEPTIONS ---------------- */
case CPU_INT_RESET: /* Reset (see Note #2). */
case CPU_INT_NMI: /* Non-maskable interrupt (see Note #2). */
case CPU_INT_HFAULT: /* Hard fault (see Note #2). */
case CPU_INT_MEM: /* Memory management (see Note #2). */
case CPU_INT_SVCALL: /* SVCall (see Note #2). */
case CPU_INT_DBGMON: /* Debug monitor (see Note #2). */
case CPU_INT_PENDSV: /* PendSV (see Note #2). */
case CPU_INT_BUSFAULT: /* Bus fault. */
case CPU_INT_USAGEFAULT: /* Usage fault. */
case CPU_INT_SYSTICK: /* SysTick. */
break;
/* ---------------- EXTERNAL INTERRUPT ---------------- */
default:
pos_max = CPU_INT_SRC_POS_MAX;
if (pos < pos_max) { /* See Note #3. */
group = (pos - 16) / 32;
nbr = (pos - 16) % 32;
CPU_CRITICAL_ENTER();
CPU_REG_NVIC_CLRPEND(group) = DEF_BIT(nbr);
CPU_CRITICAL_EXIT();
}
break;
}
}
/*$PAGE*/
/*
*********************************************************************************************************
* CPU_IntSrcPrioSet()
*
* Description : Set priority of an interrupt source.
*
* Argument(s) : pos Position of interrupt vector in interrupt table (see 'CPU_IntSrcDis()').
*
* prio Priority. Use a lower priority number for a higher priority.
*
* Return(s) : none.
*
* Caller(s) : Application.
*
* Note(s) : (1) See 'CPU_IntSrcDis() Note #1'.
*
* (2) Several interrupts priorities CANNOT be set :
*
* (a) Reset (always -3).
* (b) NMI (always -2).
* (c) Hard fault (always -1).
*
* (3) See 'CPU_IntSrcDis() Note #3'.
*********************************************************************************************************
*/
void CPU_IntSrcPrioSet (CPU_INT08U pos,
CPU_INT08U prio)
{
CPU_INT08U group;
CPU_INT08U nbr;
CPU_INT08U pos_max;
CPU_INT32U prio_32;
CPU_INT32U temp;
CPU_SR_ALLOC();
prio_32 = CPU_RevBits((CPU_INT08U)prio);
prio = (CPU_INT08U)(prio_32 >> (3 * DEF_OCTET_NBR_BITS));
switch (pos) {
case CPU_INT_STK_PTR: /* ---------------- INVALID OR RESERVED --------------- */
case CPU_INT_RSVD_07:
case CPU_INT_RSVD_08:
case CPU_INT_RSVD_09:
case CPU_INT_RSVD_10:
case CPU_INT_RSVD_13:
break;
/* ----------------- SYSTEM EXCEPTIONS ---------------- */
case CPU_INT_RESET: /* Reset (see Note #2). */
case CPU_INT_NMI: /* Non-maskable interrupt (see Note #2). */
case CPU_INT_HFAULT: /* Hard fault (see Note #2). */
break;
case CPU_INT_MEM: /* Memory management. */
CPU_CRITICAL_ENTER();
temp = CPU_REG_NVIC_SHPRI1;
temp &= ~(DEF_OCTET_MASK << (0 * DEF_OCTET_NBR_BITS));
temp |= (prio << (0 * DEF_OCTET_NBR_BITS));
CPU_REG_NVIC_SHPRI1 = temp;
CPU_CRITICAL_EXIT();
break;
case CPU_INT_BUSFAULT: /* Bus fault. */
CPU_CRITICAL_ENTER();
temp = CPU_REG_NVIC_SHPRI1;
temp &= ~(DEF_OCTET_MASK << (1 * DEF_OCTET_NBR_BITS));
temp |= (prio << (1 * DEF_OCTET_NBR_BITS));
CPU_REG_NVIC_SHPRI1 = temp;
CPU_CRITICAL_EXIT();
break;
case CPU_INT_USAGEFAULT: /* Usage fault. */
CPU_CRITICAL_ENTER();
temp = CPU_REG_NVIC_SHPRI1;
temp &= ~(DEF_OCTET_MASK << (2 * DEF_OCTET_NBR_BITS));
temp |= (prio << (2 * DEF_OCTET_NBR_BITS));
CPU_REG_NVIC_SHPRI1 = temp;
CPU_CRITICAL_EXIT();
break;
case CPU_INT_SVCALL: /* SVCall. */
CPU_CRITICAL_ENTER();
temp = CPU_REG_NVIC_SHPRI2;
temp &= ~((CPU_INT32U)DEF_OCTET_MASK << (3 * DEF_OCTET_NBR_BITS));
temp |= (prio << (3 * DEF_OCTET_NBR_BITS));
CPU_REG_NVIC_SHPRI2 = temp;
CPU_CRITICAL_EXIT();
break;
case CPU_INT_DBGMON: /* Debug monitor. */
CPU_CRITICAL_ENTER();
temp = CPU_REG_NVIC_SHPRI3;
temp &= ~(DEF_OCTET_MASK << (0 * DEF_OCTET_NBR_BITS));
temp |= (prio << (0 * DEF_OCTET_NBR_BITS));
CPU_REG_NVIC_SHPRI3 = temp;
CPU_CRITICAL_EXIT();
break;
case CPU_INT_PENDSV: /* PendSV. */
CPU_CRITICAL_ENTER();
temp = CPU_REG_NVIC_SHPRI3;
temp &= ~(DEF_OCTET_MASK << (2 * DEF_OCTET_NBR_BITS));
temp |= (prio << (2 * DEF_OCTET_NBR_BITS));
CPU_REG_NVIC_SHPRI3 = temp;
CPU_CRITICAL_EXIT();
break;
case CPU_INT_SYSTICK: /* SysTick. */
CPU_CRITICAL_ENTER();
temp = CPU_REG_NVIC_SHPRI3;
temp &= ~((CPU_INT32U)DEF_OCTET_MASK << (3 * DEF_OCTET_NBR_BITS));
temp |= (prio << (3 * DEF_OCTET_NBR_BITS));
CPU_REG_NVIC_SHPRI3 = temp;
CPU_CRITICAL_EXIT();
break;
/* ---------------- EXTERNAL INTERRUPT ---------------- */
default:
pos_max = CPU_INT_SRC_POS_MAX;
if (pos < pos_max) { /* See Note #3. */
group = (pos - 16) / 4;
nbr = (pos - 16) % 4;
CPU_CRITICAL_ENTER();
temp = CPU_REG_NVIC_PRIO(group);
temp &= ~(DEF_OCTET_MASK << (nbr * DEF_OCTET_NBR_BITS));
temp |= (prio << (nbr * DEF_OCTET_NBR_BITS));
CPU_REG_NVIC_PRIO(group) = temp;
CPU_CRITICAL_EXIT();
}
break;
}
}
/*$PAGE*/
/*
*********************************************************************************************************
* CPU_IntSrcPrioGet()
*
* Description : Get priority of an interrupt source.
*
* Argument(s) : pos Position of interrupt vector in interrupt table (see 'CPU_IntSrcDis()').
*
* Return(s) : Priority of interrupt source. If the interrupt source specified is invalid, then
* DEF_INT_16S_MIN_VAL is returned.
*
* Caller(s) : Application.
*
* Note(s) : (1) See 'CPU_IntSrcDis() Note #1'.
*
* (2) See 'CPU_IntSrcPrioSet() Note #2'.
*
* (3) See 'CPU_IntSrcDis() Note #3'.
*********************************************************************************************************
*/
CPU_INT16S CPU_IntSrcPrioGet (CPU_INT08U pos)
{
CPU_INT08U group;
CPU_INT08U nbr;
CPU_INT08U pos_max;
CPU_INT16S prio;
CPU_INT32U prio_32;
CPU_INT32U temp;
CPU_SR_ALLOC();
switch (pos) {
case CPU_INT_STK_PTR: /* ---------------- INVALID OR RESERVED --------------- */
case CPU_INT_RSVD_07:
case CPU_INT_RSVD_08:
case CPU_INT_RSVD_09:
case CPU_INT_RSVD_10:
case CPU_INT_RSVD_13:
prio = DEF_INT_16S_MIN_VAL;
break;
/* ----------------- SYSTEM EXCEPTIONS ---------------- */
case CPU_INT_RESET: /* Reset (see Note #2). */
prio = -3;
break;
case CPU_INT_NMI: /* Non-maskable interrupt (see Note #2). */
prio = -2;
break;
case CPU_INT_HFAULT: /* Hard fault (see Note #2). */
prio = -1;
break;
case CPU_INT_MEM: /* Memory management. */
CPU_CRITICAL_ENTER();
temp = CPU_REG_NVIC_SHPRI1;
prio = (temp >> (0 * DEF_OCTET_NBR_BITS)) & DEF_OCTET_MASK;
CPU_CRITICAL_EXIT();
break;
case CPU_INT_BUSFAULT: /* Bus fault. */
CPU_CRITICAL_ENTER();
temp = CPU_REG_NVIC_SHPRI1;
prio = (temp >> (1 * DEF_OCTET_NBR_BITS)) & DEF_OCTET_MASK;
CPU_CRITICAL_EXIT();
break;
case CPU_INT_USAGEFAULT: /* Usage fault. */
CPU_CRITICAL_ENTER();
temp = CPU_REG_NVIC_SHPRI1;
prio = (temp >> (2 * DEF_OCTET_NBR_BITS)) & DEF_OCTET_MASK;
break;
case CPU_INT_SVCALL: /* SVCall. */
CPU_CRITICAL_ENTER();
temp = CPU_REG_NVIC_SHPRI2;
prio = (temp >> (3 * DEF_OCTET_NBR_BITS)) & DEF_OCTET_MASK;
CPU_CRITICAL_EXIT();
break;
case CPU_INT_DBGMON: /* Debug monitor. */
CPU_CRITICAL_ENTER();
temp = CPU_REG_NVIC_SHPRI3;
prio = (temp >> (0 * DEF_OCTET_NBR_BITS)) & DEF_OCTET_MASK;
CPU_CRITICAL_EXIT();
break;
case CPU_INT_PENDSV: /* PendSV. */
CPU_CRITICAL_ENTER();
temp = CPU_REG_NVIC_SHPRI3;
prio = (temp >> (2 * DEF_OCTET_NBR_BITS)) & DEF_OCTET_MASK;
CPU_CRITICAL_EXIT();
break;
case CPU_INT_SYSTICK: /* SysTick. */
CPU_CRITICAL_ENTER();
temp = CPU_REG_NVIC_SHPRI3;
prio = (temp >> (3 * DEF_OCTET_NBR_BITS)) & DEF_OCTET_MASK;
CPU_CRITICAL_EXIT();
break;
/* ---------------- EXTERNAL INTERRUPT ---------------- */
default:
pos_max = CPU_INT_SRC_POS_MAX;
if (pos < pos_max) { /* See Note #3. */
group = (pos - 16) / 4;
nbr = (pos - 16) % 4;
CPU_CRITICAL_ENTER();
temp = CPU_REG_NVIC_PRIO(group);
CPU_CRITICAL_EXIT();
prio = (temp >> (nbr * DEF_OCTET_NBR_BITS)) & DEF_OCTET_MASK;
} else {
prio = DEF_INT_16S_MIN_VAL;
}
break;
}
if (prio >= 0) {
prio_32 = CPU_RevBits((CPU_INT32U)prio);
prio = (CPU_INT16S)(prio_32 >> (3 * DEF_OCTET_NBR_BITS));
}
return (prio);
}