Just an update to my previous post about building StrongARM tools under linux... As it turns out the "mysterious" file format the vxWorks boot loader expects is simply "coff-arm-little." After rebuilding the tools, I now have a "Hello, World" program which sends characters out the serial port. It does not use any library calls (e.g., printf). I am now in the process of getting the standard runtime libraries working. This way, I can use printf(). I'll let everyone know when this is working. In the meantime, in case anyone is interested, here's what I did to get it working: 1. Build the tools for arm-unknown-coff. I followed the steps in the CrossGCC FAQ online at http://www.objsw.com/CrossGCC/ and used GCC 2.95.2, binutils 2.9.1, and newlib 1.8.2. Before building the tools, I edited newlib-1.8.2/newlib/configure.host by commenting out both ARM_RDP_MONITOR and ARM_RDI_MONITOR. 2. Here is the program: *************************************************************************/ /* ** UART Definitions */ #define UART_SR 0x90003400 /* UART Status Register Address */ #define TXF 0x00000080 /* Transmit FIFO full bit */ #define RXR 0x00000010 /* Receive FIFO ready (not empty) */ #define UART_CR 0x90003800 /* UART Control Register Address */ #define XIE 0x00000100 /* Transmit interrupt enable bit */ #define RIE 0x00000010 /* Receive interrupt enable bit */ #define UART_DR 0x90003C00 /* UART Data Register Address */ /* ** Forward References */ static void noUartInts(void); static void putchar(int c); static void puts(char *s); static int getchar(void); /* ** Entry Point */ void __main(void) { int c; noUartInts(); puts("Hello, World!\n\r"); puts("\n\r"); puts("Enter characters to be echoed:\n\r"); while(1) { c = getchar(); if(c == '\r') { puts("\n\r"); } else { putchar(c); } } } /* ** Disable UART transmit/receive interrupts */ static void noUartInts(void) { volatile unsigned long *ptrCR; ptrCR = (volatile unsigned long *) UART_CR; *ptrCR &= ~(XIE | RIE); } /* ** Send a single character */ static void putchar(int c) { volatile unsigned long *ptrSR; volatile unsigned long *ptrDR; ptrSR = (volatile unsigned long *) UART_SR; while((*ptrSR & TXF) != 0) ; ptrDR = (volatile unsigned long *) UART_DR; *ptrDR = (unsigned long) c; } /* ** Send a null terminated string */ static void puts(char *s) { int c; while((c = *s++) != '\0') { putchar(c); } } /* ** Get a character */ static int getchar(void) { volatile unsigned long *ptrSR; volatile unsigned long *ptrDR; ptrSR = (volatile unsigned long *) UART_SR; while((*ptrSR & RXR) == 0) ; ptrDR = (volatile unsigned long *) UART_DR; return (int) *ptrDR; } /*************************************************************************/ 3. Here are the commands I used to compile the code: arm-unknown-coff-gcc -I. -nostartfiles -nodefaultlibs \ -fno-builtin -mcpu=strongarm110 -mapcs-32 -mno-sched-prolog \ -fvolatile -Wall -Wstrict-prototypes -O2 -c hw.c -o hw.o arm-unknown-coff-ld -o hw.coff hw.o -X -N -e ___main \ -Ttext 00001000 -Scott