Thread: Multiple C files, One H file

Good afternoon.
I am a hardware guy who is learning code. Can you please help me identify a problem...Using CCS and an MSP430 part. I have a rc.c (contains main) and a functions.c....I have a .h file which contains some #defines, a few const unsigned int and declarations. I also have a wrapper around all code within this file #ifndef RC_H_, #define RC_H_, #endif. Finally I have #include of the header file in both main and functions.

I am continually getting the error during compile times showing
#10056 symbol x redefined: first defined in "./functions.obj"; redefined in "./rc.obj"

Any help would be appreciated....Do you have to compile files in a certain order? Do I need to do something specific in CCS? I have found that if I exclude functions.c from the build and copy all the definitions into the header file all compiles and works...

Thanks

Code:

#include <msp430.h>
#include <stdlib.h>
#include <stdint.h>
/*
 * rc.h
 *
 *  Created on: Mar 19, 2020
 *      Author: ridge
 */

#ifndef RC_H_
#define RC_H_

//macros, etc.
const unsigned int Customer_ID = 0xa316;
const unsigned int CRC_Init = 0xFFFF;

#define PAYLOAD_SIZE 3 //does not include CRC
#define TENTHSEC 3277

#define st(x)      do { x } while (0)

#define IOconfig st(P1DIR = 0x01; /*input*/ \
                       P1OUT = 0x03; P1REN = 0xFE; /*pulldowns..p1.1 - pullup*/ \
                       P1IES = 0x02; P1IE =0xFE; /*interrupts*/ \
                       P2SEL1 |= BIT5 | BIT6; P2SEL0 &= ~(BIT5 | BIT6); /* USCI_A0 UART operation*/ \
                       P3DIR |= BIT4; P3SEL1 |= BIT4; /*output 3.4 with SMCLK*/ \
                       PJSEL0 |= BIT4 | BIT5; /*LFXT*/\
                       PM5CTL0 &= ~LOCKLPM5; P1IFG = 0x00; /*disable default Hi-Z, Must clear IFG here else P1.1 will interrupt*/)

enum switches{SW1 = 1,SW2,SW3 = 4,SW4 = 8,SW5 = 16,SW6 = 32,ALL = 64}; //ALL will flip the state of all switches

//declarations
void initClockTo16MHz(void);
void initUART(void);
unsigned int CRC(char *payload);
void initTimerB0(void);
void resetTimerSeq(void);
//unsigned int CCITT_Update(unsigned int init, unsigned int input);

#endif /* RC_H_ */

Hi Tim....
Well I would love to but....things have gone down hill quickly...I will have to get back to you on this when the error comes back...At the moment the EVM has decided it won't try and load code....

MSP430: Error initializing emulator: A firmware update is required for the MSP430 Debug Interface (MSP-FET430UIF / MSP-FET / eZ-FET). Click the "Update" button to update the firmware and launch your debug session (this may require several update steps). DO NOT UNPLUG THE INTERFACE DURING THE UPDATE.
MSP430: File Loader: Verification failed: Values at address 0x00200 do not match Please verify target memory and memory map.
MSP430: GEL: File: D:\Customers\Firmware\DSP-RC\Debug\DSP-RC.out: a data verification error occurred, file load failed.

Sorry for the inconvenience....Hoping I can resolve this
Steve

Tim...
I think I am back in business....It is not complaining so much about a line of code....Compiler spits this out

Description Resource Path Location Type
#10056 symbol "CRC_Init" redefined: first defined in "./functions.obj"; redefined in "./rc.obj" test C/C++ Problem
#10056 symbol "Customer_ID" redefined: first defined in "./functions.obj"; redefined in "./rc.obj" test C/C++ Problem

Steve

Thank you....I just ran across this....
So basically I use extern in the .h file and in the appropriate .c file I define it? Then if I do this will the other .c files be able to use this value assuming of course I put it at the top of the .c file such that it is global?

Thanks
STeve

Do I need to do the same with function definitions? Meaning I have a .c file with function definitions only. My .h file contains the declarations but I do NOT have extern before each declaration....