I'm trying to start my app from the bootloader, which is funcionally basically the same as the one in nRF5_SDK_11.0.0_89a8197.
To start the app I call bootloader_app_start(). In there the SD gets disabled, the vector table base is set to CODE_REGION_1_START and then bootloader_util_app_start(CODE_REGION_1_START) gets called. After that, nothing happens any more. As bootloader_util_app_start does not return, I don't get an error code or anything. I don't know how to proceed...
void bootloader_app_start(void)
{
ERROR_CHECK(sd_softdevice_disable());
disableInterrupts();
ERROR_CHECK(sd_softdevice_vector_table_base_set(CODE_REGION_1_START));
bootloader_util_app_start(CODE_REGION_1_START);
}
bootloader_util_app_start starts the following:
static inline void bootloader_util_reset(uint32_t start_addr)
{
__asm volatile(
"ldr r0, [%0]\t\n" // Get App initial MSP for bootloader.
"msr msp, r0\t\n" // Set the main stack pointer to the applications MSP.
"ldr r0, [%0, #0x04]\t\n" // Load Reset handler into R0.
"movs r4, #0xFF\t\n" // Move ones to R4.
"sxtb r4, r4\t\n" // Sign extend R4 to obtain 0xFFFFFFFF instead of 0xFF.
"mrs r5, IPSR\t\n" // Load IPSR to R5 to check for handler or thread mode.
"cmp r5, #0x00\t\n" // Compare, if 0 then we are in thread mode and can continue to reset handler of bootloader.
"bne isr_abort\t\n" // If not zero we need to exit current ISR and jump to reset handler of bootloader.
"mov lr, r4\t\n" // Clear the link register and set to ones to ensure no return.
"bx r0\t\n" // Branch to reset handler of bootloader.
"isr_abort: \t\n"
"mov r5, r4\t\n" // Fill with ones before jumping to reset handling. Will be popped as LR when exiting ISR. Ensures no return to application.
"mov r6, r0\t\n" // Move address of reset handler to R6. Will be popped as PC when exiting ISR. Ensures the reset handler will be executed when exist ISR.
"movs r7, #0x21\t\n" // Move MSB reset value of xPSR to R7. Will be popped as xPSR when exiting ISR. xPSR is 0x21000000 thus MSB is 0x21.
"rev r7, r7\t\n" // Reverse byte order to put 0x21 as MSB.
"push {r4-r7}\t\n" // Push everything to new stack to allow interrupt handler to fetch it on exiting the ISR.
"movs r4, #0x00\t\n" // Fill with zeros before jumping to reset handling. We be popped as R0 when exiting ISR (Cleaning up of the registers).
"movs r5, #0x00\t\n" // Fill with zeros before jumping to reset handling. We be popped as R1 when exiting ISR (Cleaning up of the registers).
"movs r6, #0x00\t\n" // Fill with zeros before jumping to reset handling. We be popped as R2 when exiting ISR (Cleaning up of the registers).
"movs r7, #0x00\t\n" // Fill with zeros before jumping to reset handling. We be popped as R3 when exiting ISR (Cleaning up of the registers).
"push {r4-r7}\t\n" // Push zeros (R4-R7) to stack to prepare for exiting the interrupt routine.
"movs r0, #0xF9\t\n" // Move the execution return command into register, 0xFFFFFFF9.
"sxtb r0, r0\t\n" // Sign extend R0 to obtain 0xFFFFFFF9 instead of 0xF9.
"bx r0\t\n" // No return - Handler mode will be exited. Stack will be popped and execution will continue in reset handler initializing other application.
".align\t\n"
:: "r" (start_addr) // Argument list for the gcc assembly. start_addr is %0.
: "r0", "r4", "r5", "r6", "r7" // List of register maintained manually.
);
}
I'm working with an Eclipse makefile Project with Cross ARM GCC on a nRF52832 with s132_nrf52_2.0.0_softdevice.hex. The app binary is the output file from eclipse and was send to the µC with my own DFU-Service from my android app. It was validated on reception and after moving it from Bank 1 to Bank 0 with a crc. The image should therefore not be the problem, I hope.
I appreciate any help, thanks!
