Hi All,
I was trying to transmit a bare-metal minimal C program to send a raw ADV_SCAN_IND PDU using nrf52840 dev board. Code is listed below:
unsigned int data = 30u;
unsigned int sum = 0u;
extern unsigned int __sflash__;
extern unsigned int __sdata__;
extern unsigned int __edata__;
extern unsigned int __sbss__;
extern unsigned int __ebss__;
int main( void );
void adv_start( void );
void startupCall( void );
volatile unsigned int zz;
void doNothing(void)
{
zz = 0u;
sum = 345;
while(1)
zz++;
}
__attribute__((section(".vectors"))) volatile unsigned int vector_table[0x100] = { 0x20000100,
(unsigned int)startupCall,
(unsigned int)doNothing,
(unsigned int)doNothing,
(unsigned int)doNothing,
(unsigned int)doNothing,
(unsigned int)doNothing,
(unsigned int)doNothing,
(unsigned int)doNothing,
(unsigned int)doNothing,
(unsigned int)doNothing,
(unsigned int)doNothing,
(unsigned int)doNothing,
(unsigned int)doNothing,
(unsigned int)doNothing,
(unsigned int)doNothing
};
// Bare metal startup
__attribute__((section(".startup"))) void copyToRam( void )
{
unsigned int * flashStart = &__sflash__;
unsigned int * ramStart = &__sdata__;
unsigned int * ramEnd = &__edata__;
while( ramStart < ramEnd )
{
*ramStart = *flashStart;
ramStart++;
flashStart++;
}
}
__attribute__((section(".startup"))) void initializeBss( void )
{
unsigned int * bssStart = &__sbss__;
unsigned int * bssEnd = &__ebss__;
while( bssStart < bssEnd )
{
*bssStart = 0u;
bssStart++;
}
}
__attribute__((section(".startup"))) void startupCall( void )
{
copyToRam();
initializeBss();
main();
}
int add( int x, int y )
{
int a;
a = x + y;
return a;
}
int main( void )
{
adv_start();
while(1);
return 0;
}
/* BLE specific code */
void init( void )
{
volatile unsigned int * pShorts = (volatile unsigned int *)(0x40001200);
volatile unsigned int * pINTSET = (volatile unsigned int *)(0x40001304);
volatile unsigned int * pFreq = (volatile unsigned int *)(0x40001508);
volatile unsigned int * pTxPower = (volatile unsigned int *)(0x4000150C);
volatile unsigned int * pMode = (volatile unsigned int *)(0x40001510);
volatile unsigned int * pPCFN0 = (volatile unsigned int *)(0x40001514);
volatile unsigned int * pPCFN1 = (volatile unsigned int *)(0x40001518);
volatile unsigned int * pBase0 = (volatile unsigned int *)(0x4000151C);
volatile unsigned int * pBase1 = (volatile unsigned int *)(0x40001520);
volatile unsigned int * pPrefix0 = (volatile unsigned int *)(0x40001524);
volatile unsigned int * pPrefix1 = (volatile unsigned int *)(0x40001528);
volatile unsigned int * pTxAddress = (volatile unsigned int *)(0x4000152C);
volatile unsigned int * pRxAddress = (volatile unsigned int *)(0x40001530);
volatile unsigned int * pCRCCNF = (volatile unsigned int *)(0x40001534);
volatile unsigned int * pCRCPOLY = (volatile unsigned int *)(0x40001538);
volatile unsigned int * pCRCINIT = (volatile unsigned int *)(0x4000153C);
volatile unsigned int * pDATAWHITE = (volatile unsigned int *)(0x40001554);
*pFreq = 0x00000050u; /* set frequency to 2480 */
*pTxPower = 0x00000000u; /* Odbm */
*pMode = 0x00000003u; /* 1Mbit BLE */
*pPCFN0 = 0x00000108u; /* LFLEN - 8, and S0LEN to 1*/
*pPCFN1 = 0x02030025u; /* Maxlen to 37 BALEN to 3 and WHITEN to 1*/
*pBase0 = 0x89BED600u; /* Base address for BLE */
*pBase1 = 0x00000000u; /* NA */
*pPrefix0 = 0x0000008Eu; /* */
*pPrefix1 = 0x00000000u; /* */
*pTxAddress = 0x00000000u; /* */
*pRxAddress = 0x00000000u; /* */
*pCRCCNF = 0x00000103u; /* 3 Byte CRC - 24 bit*/
*pCRCPOLY = 0x0000065Bu; /* BLE CRC polynomial */
*pCRCINIT = 0x00555555u; /* BLE CRC inital value */
*pDATAWHITE = 0x00000027u; /* Data whitening value for 2480MHz */
*pShorts = 0x00000003u; /* Setting up shortcut for events ready to task start and events end and task disable */
}
unsigned char payload[39] = {0x46, 0x22, 0xD3, 0xE3, 0x9B, 0xA8, 0xF7, 0xE3,
0x02, 0x01, 0x04, 0x03, 0x03, 0xAA, 0xFE, 0x14,
0x16, 0xAA, 0xFE, 0x10, 0x00, 0x00, 0x7A, 0x65,
0x70, 0x68, 0x79, 0x72, 0x70, 0x72, 0x6F, 0x6A,
0x65, 0x63, 0x74, 0x08, 0x5B, 0xA7, 0x18 };
/* Payload taken from zephyr OS project example.
First two bytes are header.
Next 6 are address and rest is data */
void send_scanable_adv( void )
{
volatile unsigned int val = 0u;
volatile unsigned int * pPacketPtr = (volatile unsigned int *)(0x40001504);
volatile unsigned int * pTasksTXEN = (volatile unsigned int *)(0x40001000);
volatile unsigned int * pTasksSTART = (volatile unsigned int *)(0x40001008);
volatile unsigned int * pEventsReady = (volatile unsigned int *)(0x40001100);
volatile unsigned int * pEventsDisabled = (volatile unsigned int *)(0x40001110);
/* Set payload */
*pPacketPtr = (unsigned int) &payload[0];
/* start transmission */
*pTasksTXEN = 0x00000001u;
/* wait for transmission to end */
while( val == 0u )
val = (unsigned int)*pEventsDisabled;
*pEventsDisabled = 0u;
}
void adv_start( void )
{
volatile int i;
init();
while(1)
{
sum++;
send_scanable_adv();
for( i = 0; i < 10000; i++ ); //Delay before next packet transmission
}
}
Here is the linker script used
MEMORY
{
FLASH (rx) : ORIGIN = 0x00000000, LENGTH = 0x1000
SRAM (rwx) : ORIGIN = 0x20000100, LENGTH = 0x400
}
SECTIONS {
.vectors : { * (.vectors); } > FLASH
.startup : { * (.startup); } > FLASH
.text : { * (.text) ; } > FLASH
.rodata : { * (.rodata) ; __sflash__ = .; } > FLASH
.data : { __sdata__ = .; * (.data) ; __edata__ = .; } > SRAM AT>FLASH
.bss : { __sbss__ = .; * (.bss) ; __ebss__ = .; } > SRAM
__ebss__ = .;
}
Build script used to compile is here:
echo "Running Compiler" echo "arm-none-eabi-gcc -g -nostdlib -T sample.ld -mcpu=cortex-m0 -mthumb main.c -o startup.elf" arm-none-eabi-gcc -g -nostdlib -T sample.ld -mcpu=cortex-m4 -mthumb main.c -o startup.elf echo "Creating Binary" echo "arm-none-eabi-objcopy -O binary startup.elf startup.bin" arm-none-eabi-objcopy -O binary startup.elf startup.bin echo "Listing Symbols" echo "arm-none-eabi-nm startup.elf" arm-none-eabi-nm startup.elf
Code runs without any issues but I could not see the packet on BLE sniffer. Anyone has any idea why I am not able to see the packets on a BLE sniffer.
Regards
S
