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olivier
Joined: 08 Apr 2010 Posts: 11
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error on my compiler 4.100 |
Posted: Tue May 24, 2011 8:37 am |
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Hi everyone,
I am a new C programmer and i write a simple code but already have problem.
the error message says that "Error 51, a numeric expression must be here".
this happen right at my variable delaration such as int and float.
below is my code
#include "C:\Microcontroller Firmware Center\main-18F.h"
#include "C:\Microcontroller Firmware Center\Flex_LCD.c"
#include <float.h>
#include <limits.h>
#include <math.h>
#include <stdio.h>
#include <stddef.h>
#include <stdlib.h>
#include <stdlibm.h>
#include <string.h>
#define START_BUTTON PIN_C0
#define STOP_BUTTON PIN_B0
#define STATUS_LED PIN_C1
#define EXEC_STATUS PIN_C2
void Blink_LED (int flash_time, int flash_delay);
void LCD_Test();
void main()
{
setup_adc_ports(AN0|VSS_VDD);
setup_adc(ADC_CLOCK_DIV_4|ADC_TAD_MUL_20);
setup_psp(PSP_DISABLED);
setup_spi(SPI_SS_DISABLED);
setup_wdt(WDT_OFF);
setup_timer_0(RTCC_INTERNAL);
setup_timer_1(T1_DISABLED);
setup_timer_2(T2_DISABLED,0,1);
setup_comparator(NC_NC_NC_NC);
setup_vref(FALSE);
// setup_oscillator(OSC_20MHZ|OSC_INTRC|OSC_31250|OSC_PLL_ON);
// TODO: USER CODE!!
lcd_init();
LCD_Test();
float Pressure_Sensor_Scale = 0.0005; <---- Error happen at this point.
float data_in = 0, Pressure_Read = 0, Vref = 5.000, adc_resolution = 1023.00;
set_adc_channel(0);
output_high(STATUS_LED);
printf("Press START_BUTTON NOW!\n\r");
while (TRUE)
{
while (input(START_BUTTON) == 1 )
{
// output_toggle(STATUS_LED);
// delay_ms(100);
;
}
// Blink_LED (3,100);
// data_in = read_adc();
data_in = (float)(read_adc() * Vref)/adc_resolution;
Pressure_Read = (float)(data_in / Pressure_Sensor_Scale);
printf("Sensor Output Voltage is: %3.3fV \n\r", data_in);
printf(lcd_putc, "Pressure Read is: %3.3f PSI \n\r", Pressure_Read);
printf(lcd_putc, "\fThis is the 1st line"); |
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FvM
Joined: 27 Aug 2008 Posts: 2337 Location: Germany
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Posted: Tue May 24, 2011 9:08 am |
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Although some CCS C versions tolerate it, the C standard (in contrast to C++) doesn't allow variable declarations in the middle of the code. |
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olivier
Joined: 08 Apr 2010 Posts: 11
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Posted: Tue May 24, 2011 9:27 am |
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FvM wrote: | Although some CCS C versions tolerate it, the C standard (in contrast to C++) doesn't allow variable declarations in the middle of the code. |
thank you for replying me back. I have a CCS compiler. and as you mention, it should tolerate my define the variable however it was not.
i try it at the top and it work. so weird. same compiler but at different computer does not work the same. |
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Ttelmah
Joined: 11 Mar 2010 Posts: 19513
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Posted: Wed May 25, 2011 2:10 am |
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Though the later compilers will tolerate declarations inside the code. You _must_ still always declare variables before they are used.
This is why it fails in what you post.
It is always better to stick to C syntax and declare at the start. It makes the code portable to other C's, and avoids this type of problem.
Best Wishes |
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