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Hi there, Iam using Keil uVision3(MDK 3.11) with GNU compiler for my LPC2368 based project.
Iam seeing the following error (undefined reference to '__udivsi3') and warnings( missing braces around initializer) :
Build target 'MCB2300' assembling Startup.s... compiling LPC2000_CAN_Driver.c... src/LPC2000_CAN_Driver.c(72): warning: missing braces around initializer src/LPC2000_CAN_Driver.c(72): warning: (near initialization for 'CAN_Send_Data[0].DataField') compiling target.c... compiling irq.c... compiling LPC2000_CAN_SYS.c... linking... lpc2000_can_sys.o(.text+0x21c): In function 'uart0_config': src/LPC2000_CAN_SYS.c(225): error: undefined reference to '__udivsi3' collect2: ld returned 1 exit status Target not created
The error message points to the code line "temp_uart0 = (Fpclk/16)/Baudrate; " in the following source code :
void uart0_config(UInt32 Baudrate,UART0MODE U0_config) { UInt32 temp_uart0; U0LCR = 0x80; // DLAB=1, Can use U0DLM, U0DLL temp_uart0 = (Fpclk/16)/Baudrate; U0DLM = temp_uart0>>8; U0DLL = temp_uart0&0xFF; temp_uart0 = U0_config.Datalength - 5; if( U0_config.Stopbit == 2 ) temp_uart0 |= 0x04; if( U0_config.Paritybit != 0 ) { U0_config.Paritybit = U0_config.Paritybit - 1; temp_uart0 |= 0x08; } temp_uart0 |= U0_config.Paritybit<<4; U0LCR = temp_uart0; U0FCR = 0x07; U0IER = IER_RBR | IER_RLS; }
The warning points to the following code:
lpc2000CANdriver_TXObj_t CAN_Send_Data[] = {{0x00080000,0x00000001,0x12345678,0x12345678}, {0x00080000,0x00000002,0x12345678,0x12345678}, {0x00080000,0x00000347,0x12345678,0x12345678}, {0x00080000,0x000003F1,0x1643F6E5,0xD4C3B2A1}};
I have observed that, in the Linker settings if the option "Donot use Standard system libraries" is not selected then the error is not reported by the compiler. But, the UART doesnot work.
I have tried out the same program using Real View Compiler and it works fine.
Kindly give me your suggestions.
These are just matters of style:
Rather than use "magic numbers" like 48 and 55, your code would be more readable if you used '0' and 'A' as character constants.
Similarly for the 0x20 "magic number" in (U0LSR & 0x20)
As the name of the function is "Print_4bits_to_Screen", its valid input range should just be 0x0 to 0xF - so what is your intention for cases 32, 44, and 45?! The name of the function should clearly identify what it does - anything non-obvious (like this) that can't be expressed in the function name should be clearly stated in a header comment for the function
Switching compilers means that you had to use different start-up files. You may not be doing the same chip initialisation in both cases.
I'd guess that the resultant baud rate is dependant on the core frequency and that this is now different.
This is sometimes set-up in the start-up file. Could this be the case?
Yes Patrick, you are correct. Thank You all, for the guidance. I have set right the baud rate in the startup file. Now it's working fine.
Can some one please give me suggestions regarding the Compilation warnings.
You must have the following switch enabled.
Either remove the switch or change the code.
-Wmissing-braces Warn if an aggregate or union initializer is not fully bracketed. In the following example, the initializer for 'a' is not fully bracketed, but that for 'b' is fully bracketed. int a[2][2] = { 0, 1, 2, 3 }; int b[2][2] = { { 0, 1 }, { 2, 3 } }; This warning is enabled by '-Wall'.
But he said the code causing the warning was:
lpc2000CANdriver_TXObj_t CAN_Send_Data[] = { {0x00080000,0x00000001,0x12345678,0x12345678}, {0x00080000,0x00000002,0x12345678,0x12345678}, {0x00080000,0x00000347,0x12345678,0x12345678}, {0x00080000,0x000003F1,0x1643F6E5,0xD4C3B2A1} };
Which seems to have too many braces, rather than too few!
That's not true to say unless you're assuming that lpc2000CANdriver_TXObj_t is a scalar type.
If it was, the compiler would have complained differently.
It's probably a structure with complex elements that need to be bracketed like the example below.
lpc2000CANdriver_TXObj_t CAN_Send_Data[] = { {0x00080000,0x00000001,{0x12345678,0x12345678}}, {0x00080000,0x00000002, {0x12345678,0x12345678}}, {0x00080000,0x00000347, {0x12345678,0x12345678}}, {0x00080000,0x000003F1, {0x1643F6E5,0xD4C3B2A1}} };
"you're assuming that lpc2000CANdriver_TXObj_t is a scalar type."
Ah yes - I was!