[参考译文] TMS320F2800157-Q1：将负浮点值转换为 int 时取零

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https://e2e.ti.com/support/microcontrollers/c2000-microcontrollers-group/c2000/f/c2000-microcontrollers-forum/1399529/tms320f2800157-q1-get-zero-while-convert-a-negative-float-value-to-int

器件型号：TMS320F2800157-Q1

工具与软件：

大家好、专家：

客户反馈、他尝试显式将 float 变量转换为整数、如果 float 的值为负、则转换后的整数的值为0。但根据他对 C 编程语言中的数据类型的理解、应将其解析为负有符号整数(如果转换为有符号整数)或大无符号整数(如果转换为无符号整数)。

我做了一个简单的测试并得到了类似的结果。请帮助阐明 C2000器件上将负浮点型转换为整数型时的预期行为。如果有一些相关文档可以指导客户、那将是完美的。

谢谢。

下面是我的测试代码、以及每个变量的值的屏幕截图。

//#############################################################################
//
// FILE:   empty_driverlib_main.c
//
//! \addtogroup driver_example_list
//! <h1>Empty Project Example</h1> 
//!
//! This example is an empty project setup for Driverlib development.
//!
//
//#############################################################################
//
//
// $Copyright:
// Copyright (C) 2024 Texas Instruments Incorporated - http://www.ti.com/
//
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// modification, are permitted provided that the following conditions 
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// 
//   Redistributions of source code must retain the above copyright 
//   notice, this list of conditions and the following disclaimer.
// 
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//   notice, this list of conditions and the following disclaimer in the 
//   documentation and/or other materials provided with the   
//   distribution.
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//   its contributors may be used to endorse or promote products derived
//   from this software without specific prior written permission.
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// $
//#############################################################################

//
// Included Files
//
#include "driverlib.h"
#include "device.h"
#include "board.h"
#include "c2000ware_libraries.h"

float f1 = 1.2345;
float f2 = -6.789;
unsigned int u1 = 0;
unsigned int u2 = 0;
signed int s1 = 0;
signed int s2 = 0;

//
// Main
//
void main(void)
{

    //
    // Initialize device clock and peripherals
    //
    Device_init();

    //
    // Disable pin locks and enable internal pull-ups.
    //
    Device_initGPIO();

    //
    // Initialize PIE and clear PIE registers. Disables CPU interrupts.
    //
    Interrupt_initModule();

    //
    // Initialize the PIE vector table with pointers to the shell Interrupt
    // Service Routines (ISR).
    //
    Interrupt_initVectorTable();

    //
    // PinMux and Peripheral Initialization
    //
    Board_init();

    //
    // C2000Ware Library initialization
    //
    C2000Ware_libraries_init();

    //
    // Enable Global Interrupt (INTM) and real time interrupt (DBGM)
    //
    EINT;
    ERTM;

    while(1)
    {
        u1 = (unsigned int)f1;
        u2 = (unsigned int)f2;
        s1 = (unsigned int)f1;
        s2 = (unsigned int)f2;
        
    }
}

//
// End of File
//