Create a blank new project using CMSIS library

..\..\..\Drivers\source\lpc17xx_gpio.c(617): warning: #186-D: pointless comparison of unsigned integer with zero

The below line in red is the line 617 of lpc17xx_gpio.c.

/*********************************************************************//**
 * @brief               Set direction for FIO port in byte accessible style
 * @param[in]   portNum         Port number, in range from 0 to 4
 * @param[in]   byteNum         Byte part number, should be in range from 0 to 3
 * @param[in]   bitValue        Value that contains all bits in to set direction,
 *                                                      in range from 0 to 0xFF.
 * @param[in]   dir                     Direction value, should be:
 *                                                      - 0: Input.
 *                                                      - 1: Output.
 * @return              None
 *
 * Note: All remaining bits that are not activated in bitValue (value '0')
 * will not be effected by this function.
 **********************************************************************/
void FIO_ByteSetDir(uint8_t portNum, uint8_t byteNum, uint8_t bitValue, uint8_t dir)
{
        GPIO_Byte_TypeDef *pFIO = FIO_ByteGetPointer(portNum);
        if(pFIO != NULL) {
                // Output direction
                if (dir) {
                        if ((byteNum >= 0) && (byteNum <= 3)) {
                                pFIO->FIODIR[byteNum] |= bitValue;
                        }
                }
                // Input direction
                else {
                        if ((byteNum >= 0) && (byteNum <= 3)) {
                                pFIO->FIODIR[byteNum] &= ~bitValue;
                        }
                }
        }
}

..\..\..\Drivers\source\lpc17xx_gpio.c(617): warning: #186-D: pointless comparison of unsigned integer with zero

The below line in red is the line 617 of lpc17xx_gpio.c.

/*********************************************************************//**
 * @brief               Set direction for FIO port in byte accessible style
 * @param[in]   portNum         Port number, in range from 0 to 4
 * @param[in]   byteNum         Byte part number, should be in range from 0 to 3
 * @param[in]   bitValue        Value that contains all bits in to set direction,
 *                                                      in range from 0 to 0xFF.
 * @param[in]   dir                     Direction value, should be:
 *                                                      - 0: Input.
 *                                                      - 1: Output.
 * @return              None
 *
 * Note: All remaining bits that are not activated in bitValue (value '0')
 * will not be effected by this function.
 **********************************************************************/
void FIO_ByteSetDir(uint8_t portNum, uint8_t byteNum, uint8_t bitValue, uint8_t dir)
{
        GPIO_Byte_TypeDef *pFIO = FIO_ByteGetPointer(portNum);
        if(pFIO != NULL) {
                // Output direction
                if (dir) {
                        if ((byteNum >= 0) && (byteNum <= 3)) {
                                pFIO->FIODIR[byteNum] |= bitValue;
                        }
                }
                // Input direction
                else {
                        if ((byteNum >= 0) && (byteNum <= 3)) {
                                pFIO->FIODIR[byteNum] &= ~bitValue;
                        }
                }
        }
}

..\..\..\..\Drivers\source\lpc17xx_timer.c(108): warning: #68-D: integer conversion resulted in a change of sign

The below line in red is the line 108 of lpc17xx_timer.c.

/*********************************************************************//**
 * @brief         Convert a timer register pointer to a timer number
 * @param[in]    TIMx Pointer to LPC_TIM_TypeDef, should be:
 *                 - LPC_TIM0: TIMER0 peripheral
 *                 - LPC_TIM1: TIMER1 peripheral
 *                 - LPC_TIM2: TIMER2 peripheral
 *                 - LPC_TIM3: TIMER3 peripheral
 * @return         The timer number (0 to 3) or -1 if register pointer is bad
 **********************************************************************/
uint32_t converPtrToTimeNum (LPC_TIM_TypeDef *TIMx)
{
    uint32_t tnum = -1;

    if (TIMx == LPC_TIM0)
    {
        tnum = 0;
    }
    else if (TIMx == LPC_TIM1)
    {
        tnum = 1;
    }
    else if (TIMx == LPC_TIM2)
    {
        tnum = 2;
    }
    else if (TIMx == LPC_TIM3)
    {
        tnum = 3;
    }

    return tnum;
}

Why set it to -1?

The "header" comment at the start of the function tells you that:

/*********************************************************************//**
 * @brief         Convert a timer register pointer to a timer number
 * @param[in]    TIMx Pointer to LPC_TIM_TypeDef, should be:
 *                 - LPC_TIM0: TIMER0 peripheral
 *                 - LPC_TIM1: TIMER1 peripheral
 *                 - LPC_TIM2: TIMER2 peripheral
 *                 - LPC_TIM3: TIMER3 peripheral
 * @return         The timer number (0 to 3) or -1 if register pointer is bad
 **********************************************************************/

So this is clearly a coding error - the function cannot possibly ever return a negative value, as its return type is defined as unsigned!!

This is a perfect example of why ignoring warnings is a Bad Thing!

As I said earlier, whoever allowed this to be releaed should be shot!

should be "released", of course!

Well, not the first package of bad ARM code from NXP. I did look at the source code packages for LPC21xx and LPC23xx and decided to ignore them completely and just make use of the chip manual and write my own code.