mirror of
https://github.com/mytechnotalent/Embedded-Hacking.git
synced 2026-08-27 21:30:37 +02:00
feat: add 0x0b_spi_cbm bare-metal SPI loopback driver
This commit is contained in:
Kevin Thomas
@@ -0,0 +1,35 @@
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/**
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******************************************************************************
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* @file image_def.c
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* @author Kevin Thomas
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* @brief RP2350 IMAGE_DEF block for boot ROM image recognition.
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*
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* Must appear within the first 4 KB of flash for the boot ROM
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* to accept the image.
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*
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******************************************************************************
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* @attention
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*
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* Copyright (c) 2026 Kevin Thomas.
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* All rights reserved.
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*
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* This software is licensed under terms that can be found in the LICENSE file
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* in the root directory of this software component.
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* If no LICENSE file comes with this software, it is provided AS-IS.
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*
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******************************************************************************
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*/
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#include <stdint.h>
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/**
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* @brief IMAGE_DEF block structure placed in flash
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*/
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__attribute__((section(".embedded_block"), used))
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const uint8_t picobin_block[] = {
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0xD3, 0xDE, 0xFF, 0xFF,
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0x42, 0x01, 0x21, 0x10,
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0xFF, 0x01, 0x00, 0x00,
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0x00, 0x00, 0x00, 0x00,
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0x79, 0x35, 0x12, 0xAB
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};
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@@ -0,0 +1,122 @@
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/**
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******************************************************************************
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* @file main.c
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* @author Kevin Thomas
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* @brief SPI loopback demonstration.
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*
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* Performs a full-duplex SPI0 transfer in master mode with
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* MOSI wired to MISO for loopback verification. Prints TX
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* and RX data over UART every second.
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*
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* Wiring (loopback test):
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* GPIO0 -> UART TX (USB-to-UART adapter RX)
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* GPIO1 -> UART RX (USB-to-UART adapter TX)
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* GPIO19 (MOSI) -> GPIO16 (MISO)
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* GPIO18 (SCK) -> logic analyzer (optional)
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* GPIO17 (CS) -> active-low slave (optional)
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*
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******************************************************************************
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* @attention
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*
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* Copyright (c) 2026 Kevin Thomas.
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* All rights reserved.
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*
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* This software is licensed under terms that can be found in the LICENSE file
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* in the root directory of this software component.
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* If no LICENSE file comes with this software, it is provided AS-IS.
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*
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******************************************************************************
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*/
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#include "rp2350_spi.h"
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#include "rp2350_uart.h"
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#include "rp2350_delay.h"
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#include "rp2350_xosc.h"
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/**
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* @brief Hex digit lookup table for byte-to-hex conversion.
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*/
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static const char _hex_lut[16] = "0123456789ABCDEF";
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/**
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* @brief Print a byte as a two-digit hex string over UART.
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* @param value byte to print
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* @retval None
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*/
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static void _print_hex(uint8_t value)
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{
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char buf[3];
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buf[0] = _hex_lut[value >> 4];
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buf[1] = _hex_lut[value & 0x0FU];
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buf[2] = '\0';
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uart_puts(buf);
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}
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/**
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* @brief Print a buffer as hex bytes separated by spaces over UART.
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* @param label text label to print before the data
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* @param buf byte buffer to print
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* @param len number of bytes in buffer
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* @retval None
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*/
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static void _print_buffer(const char *label, const uint8_t *buf, uint32_t len)
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{
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uart_puts(label);
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for (uint32_t i = 0; i < len; i++) {
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_print_hex(buf[i]);
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if (i + 1 < len)
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uart_putchar(' ');
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}
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uart_puts("\r\n");
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}
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/**
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* @brief Perform one SPI loopback transfer and print TX/RX over UART.
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* @param tx_buf transmit buffer
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* @param rx_buf receive buffer (cleared after printing)
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* @param len number of bytes to transfer
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* @retval None
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*/
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static void _loopback_transfer(const uint8_t *tx_buf, uint8_t *rx_buf, uint32_t len)
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{
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spi_cs_select();
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spi_transfer(tx_buf, rx_buf, len);
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spi_cs_deselect();
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_print_buffer("TX: ", tx_buf, len);
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_print_buffer("RX: ", rx_buf, len);
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uart_puts("\r\n");
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}
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/**
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* @brief Clear a byte buffer to zero.
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* @param buf pointer to buffer
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* @param len number of bytes to clear
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* @retval None
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*/
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static void _clear_buffer(uint8_t *buf, uint32_t len)
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{
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for (uint32_t i = 0; i < len; i++)
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buf[i] = 0;
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}
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/**
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* @brief Application entry point for the SPI loopback demo.
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* @retval int does not return
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*/
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int main(void)
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{
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/** @brief Transmit test pattern for SPI loopback. */
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static const uint8_t tx[] = {0xDE, 0xAD, 0xBE, 0xEF};
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/** @brief Buffer length for SPI loopback transfer. */
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static const uint32_t len = sizeof(tx);
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uint8_t rx[sizeof(tx)] = {0};
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xosc_set_clk_ref();
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spi_release_reset();
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spi_init();
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uart_puts("SPI loopback initialized (MOSI->MISO on GPIO19->GPIO16)\r\n");
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while (1) {
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_loopback_transfer(tx, rx, len);
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_clear_buffer(rx, len);
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delay_ms(1000);
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}
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}
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@@ -0,0 +1,34 @@
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/**
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******************************************************************************
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* @file rp2350_coprocessor.c
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* @author Kevin Thomas
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* @brief Coprocessor access control driver implementation for RP2350.
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*
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* Grants access to coprocessors 0 and 1 by setting the
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* corresponding bits in CPACR with DSB/ISB barriers.
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*
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******************************************************************************
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* @attention
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*
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* Copyright (c) 2026 Kevin Thomas.
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* All rights reserved.
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*
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* This software is licensed under terms that can be found in the LICENSE file
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* in the root directory of this software component.
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* If no LICENSE file comes with this software, it is provided AS-IS.
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*
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******************************************************************************
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*/
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#include "rp2350_coprocessor.h"
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void coprocessor_enable(void)
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{
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uint32_t value;
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value = *CPACR;
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value |= (1U << CPACR_CP1_SHIFT);
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value |= (1U << CPACR_CP0_SHIFT);
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*CPACR = value;
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__asm__ volatile ("dsb");
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__asm__ volatile ("isb");
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}
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@@ -0,0 +1,55 @@
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/**
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******************************************************************************
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* @file rp2350_delay.c
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* @author Kevin Thomas
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* @brief Delay driver implementation for RP2350.
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*
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* Busy-wait millisecond and microsecond delays calibrated for
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* a 12 MHz clock.
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*
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******************************************************************************
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* @attention
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*
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* Copyright (c) 2026 Kevin Thomas.
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* All rights reserved.
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*
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* This software is licensed under terms that can be found in the LICENSE file
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* in the root directory of this software component.
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* If no LICENSE file comes with this software, it is provided AS-IS.
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*
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******************************************************************************
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*/
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#include "rp2350_delay.h"
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void delay_ms(uint32_t ms)
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{
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if (ms == 0)
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return;
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__asm__ volatile (
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"mov r4, #3600\n\t"
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"mul r5, %0, r4\n\t"
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"1:\n\t"
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"subs r5, #1\n\t"
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"bne 1b\n\t"
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:
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: "r" (ms)
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: "r4", "r5", "cc"
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);
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}
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void delay_us(uint32_t us)
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{
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if (us == 0)
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return;
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__asm__ volatile (
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"mov r4, #4\n\t"
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"mul r5, %0, r4\n\t"
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"1:\n\t"
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"subs r5, #1\n\t"
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"bne 1b\n\t"
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:
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: "r" (us)
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: "r4", "r5", "cc"
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);
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}
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@@ -0,0 +1,33 @@
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/**
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******************************************************************************
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* @file rp2350_reset.c
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* @author Kevin Thomas
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* @brief Reset controller driver implementation for RP2350.
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*
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* Releases IO_BANK0 from reset and waits until the subsystem
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* is ready.
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*
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******************************************************************************
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* @attention
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*
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* Copyright (c) 2026 Kevin Thomas.
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* All rights reserved.
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*
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* This software is licensed under terms that can be found in the LICENSE file
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* in the root directory of this software component.
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* If no LICENSE file comes with this software, it is provided AS-IS.
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*
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******************************************************************************
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*/
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#include "rp2350_reset.h"
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void reset_init_subsystem(void)
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{
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uint32_t value;
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value = RESETS->RESET;
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value &= ~(1U << RESETS_RESET_IO_BANK0_SHIFT);
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RESETS->RESET = value;
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while ((RESETS->RESET_DONE & (1U << RESETS_RESET_IO_BANK0_SHIFT)) == 0) {
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}
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}
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@@ -0,0 +1,47 @@
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/**
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******************************************************************************
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* @file rp2350_reset_handler.c
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* @author Kevin Thomas
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* @brief Reset handler implementation for RP2350.
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*
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* Entry point after power-on or system reset. Initializes the
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* stack, XOSC, subsystem resets, UART, coprocessor, then
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* branches to main().
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*
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******************************************************************************
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* @attention
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*
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* Copyright (c) 2026 Kevin Thomas.
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* All rights reserved.
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*
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* This software is licensed under terms that can be found in the LICENSE file
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* in the root directory of this software component.
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* If no LICENSE file comes with this software, it is provided AS-IS.
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*
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******************************************************************************
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*/
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#include "rp2350_reset_handler.h"
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#include "rp2350_stack.h"
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#include "rp2350_xosc.h"
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#include "rp2350_reset.h"
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#include "rp2350_spi.h"
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#include "rp2350_uart.h"
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#include "rp2350_coprocessor.h"
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extern int main(void);
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void __attribute__((naked, noreturn)) Reset_Handler(void)
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{
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__asm__ volatile (
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"bl stack_init\n\t"
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"bl xosc_init\n\t"
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"bl xosc_enable_peri_clk\n\t"
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"bl reset_init_subsystem\n\t"
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"bl spi_release_reset\n\t"
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"bl uart_release_reset\n\t"
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"bl uart_init\n\t"
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"bl coprocessor_enable\n\t"
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"b main\n\t"
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);
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}
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@@ -0,0 +1,205 @@
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/**
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******************************************************************************
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* @file rp2350_spi.c
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* @author Kevin Thomas
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* @brief SPI0 master driver implementation for RP2350.
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*
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* Full-duplex SPI0 master on GPIO16 (MISO), GPIO17 (CS),
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* GPIO18 (SCK), GPIO19 (MOSI). Motorola SPI frame format,
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* 8-bit data, CPOL=0, CPHA=0, 1 MHz clock from 12 MHz
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* clk_peri.
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*
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******************************************************************************
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* @attention
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*
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* Copyright (c) 2026 Kevin Thomas.
|
||||
* All rights reserved.
|
||||
*
|
||||
* This software is licensed under terms that can be found in the LICENSE file
|
||||
* in the root directory of this software component.
|
||||
* If no LICENSE file comes with this software, it is provided AS-IS.
|
||||
*
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******************************************************************************
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*/
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#include "rp2350_spi.h"
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/**
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* @brief Bit mask for the chip-select pin.
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*/
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#define CS_PIN_MASK (1U << SPI_CS_PIN)
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/**
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* @brief Clear the SPI0 reset bit in the reset controller.
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* @retval None
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*/
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static void _spi_clear_reset(void)
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{
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uint32_t value;
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value = RESETS->RESET;
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value &= ~(1U << RESETS_RESET_SPI0_SHIFT);
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RESETS->RESET = value;
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}
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/**
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* @brief Wait until SPI0 is out of reset.
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* @retval None
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*/
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static void _spi_wait_reset_done(void)
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{
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while ((RESETS->RESET_DONE & (1U << RESETS_RESET_SPI0_SHIFT)) == 0) {
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}
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}
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/**
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* @brief Configure a GPIO pad for SPI: input enabled, no pull, no isolation.
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* @param pin GPIO pin number to configure
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* @retval None
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*/
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static void _configure_spi_pad(uint8_t pin)
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{
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uint32_t value;
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value = PADS_BANK0->GPIO[pin];
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value &= ~(1U << PADS_BANK0_OD_SHIFT);
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value |= (1U << PADS_BANK0_IE_SHIFT);
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value &= ~(1U << PADS_BANK0_ISO_SHIFT);
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PADS_BANK0->GPIO[pin] = value;
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}
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/**
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* @brief Configure a GPIO pad for CS: output enabled, pull-up, no isolation.
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* @param pin GPIO pin number to configure
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* @retval None
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*/
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static void _configure_cs_pad(uint8_t pin)
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{
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uint32_t value;
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value = PADS_BANK0->GPIO[pin];
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value &= ~(1U << PADS_BANK0_OD_SHIFT);
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value |= (1U << PADS_BANK0_IE_SHIFT);
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value |= (1U << PADS_BANK0_PUE_SHIFT);
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value &= ~(1U << PADS_BANK0_ISO_SHIFT);
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PADS_BANK0->GPIO[pin] = value;
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}
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|
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/**
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* @brief Set a GPIO funcsel to SPI alternate function.
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* @param pin GPIO pin number
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* @retval None
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*/
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static void _set_funcsel_spi(uint8_t pin)
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{
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IO_BANK0->GPIO[pin].CTRL = IO_BANK0_CTRL_FUNCSEL_SPI;
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}
|
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|
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/**
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* @brief Set a GPIO funcsel to SIO for software control (CS pin).
|
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* @param pin GPIO pin number
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* @retval None
|
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*/
|
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static void _set_funcsel_sio(uint8_t pin)
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{
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IO_BANK0->GPIO[pin].CTRL = IO_BANK0_CTRL_FUNCSEL_SIO;
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}
|
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|
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/**
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* @brief Configure CS pin as output, initially deasserted (high).
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* @retval None
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*/
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static void _cs_init(void)
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{
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SIO[SIO_GPIO_OUT_SET_OFFSET] = CS_PIN_MASK;
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SIO[SIO_GPIO_OE_SET_OFFSET] = CS_PIN_MASK;
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}
|
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|
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/**
|
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* @brief Configure SSPCR0 for 8-bit Motorola SPI, SCR=0.
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* @retval None
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*/
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static void _configure_cr0(void)
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{
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uint32_t value = 0;
|
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value |= (SPI_SSPCR0_DSS_8BIT << SPI_SSPCR0_DSS_SHIFT);
|
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value |= (SPI_SCR_1MHZ << SPI_SSPCR0_SCR_SHIFT);
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SPI0->SSPCR0 = value;
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}
|
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|
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/**
|
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* @brief Configure SSPCPSR clock prescaler for 1 MHz.
|
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* @retval None
|
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*/
|
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static void _configure_prescaler(void)
|
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{
|
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SPI0->SSPCPSR = SPI_CPSDVSR_1MHZ;
|
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}
|
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|
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/**
|
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* @brief Enable the SPI0 peripheral (SSE=1 in SSPCR1).
|
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* @retval None
|
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*/
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static void _enable_spi(void)
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{
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SPI0->SSPCR1 = (1U << SPI_SSPCR1_SSE_SHIFT);
|
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}
|
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|
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/**
|
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* @brief Wait until the SPI transmit FIFO has space.
|
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* @retval None
|
||||
*/
|
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static void _wait_tx_not_full(void)
|
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{
|
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while ((SPI0->SSPSR & SPI_SSPSR_TNF_MASK) == 0) {
|
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}
|
||||
}
|
||||
|
||||
/**
|
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* @brief Wait until the SPI receive FIFO has data.
|
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* @retval None
|
||||
*/
|
||||
static void _wait_rx_not_empty(void)
|
||||
{
|
||||
while ((SPI0->SSPSR & SPI_SSPSR_RNE_MASK) == 0) {
|
||||
}
|
||||
}
|
||||
|
||||
void spi_release_reset(void)
|
||||
{
|
||||
_spi_clear_reset();
|
||||
_spi_wait_reset_done();
|
||||
}
|
||||
|
||||
void spi_init(void)
|
||||
{
|
||||
_configure_spi_pad(SPI_MOSI_PIN);
|
||||
_configure_spi_pad(SPI_MISO_PIN);
|
||||
_configure_spi_pad(SPI_SCK_PIN);
|
||||
_configure_cs_pad(SPI_CS_PIN);
|
||||
_set_funcsel_spi(SPI_MOSI_PIN);
|
||||
_set_funcsel_spi(SPI_MISO_PIN);
|
||||
_set_funcsel_spi(SPI_SCK_PIN);
|
||||
_set_funcsel_sio(SPI_CS_PIN);
|
||||
_cs_init();
|
||||
_configure_cr0();
|
||||
_configure_prescaler();
|
||||
_enable_spi();
|
||||
}
|
||||
|
||||
void spi_cs_select(void)
|
||||
{
|
||||
SIO[SIO_GPIO_OUT_CLR_OFFSET] = CS_PIN_MASK;
|
||||
}
|
||||
|
||||
void spi_cs_deselect(void)
|
||||
{
|
||||
SIO[SIO_GPIO_OUT_SET_OFFSET] = CS_PIN_MASK;
|
||||
}
|
||||
|
||||
void spi_transfer(const uint8_t *tx, uint8_t *rx, uint32_t len)
|
||||
{
|
||||
for (uint32_t i = 0; i < len; i++) {
|
||||
_wait_tx_not_full();
|
||||
SPI0->SSPDR = tx[i];
|
||||
_wait_rx_not_empty();
|
||||
rx[i] = (uint8_t)SPI0->SSPDR;
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,38 @@
|
||||
/**
|
||||
******************************************************************************
|
||||
* @file rp2350_stack.c
|
||||
* @author Kevin Thomas
|
||||
* @brief Stack pointer initialization for RP2350.
|
||||
*
|
||||
* Sets MSP, PSP, MSPLIM, and PSPLIM using inline assembly.
|
||||
*
|
||||
******************************************************************************
|
||||
* @attention
|
||||
*
|
||||
* Copyright (c) 2026 Kevin Thomas.
|
||||
* All rights reserved.
|
||||
*
|
||||
* This software is licensed under terms that can be found in the LICENSE file
|
||||
* in the root directory of this software component.
|
||||
* If no LICENSE file comes with this software, it is provided AS-IS.
|
||||
*
|
||||
******************************************************************************
|
||||
*/
|
||||
|
||||
#include "rp2350_stack.h"
|
||||
|
||||
void stack_init(void)
|
||||
{
|
||||
__asm__ volatile (
|
||||
"ldr r0, =%0\n\t"
|
||||
"msr PSP, r0\n\t"
|
||||
"ldr r0, =%1\n\t"
|
||||
"msr MSPLIM, r0\n\t"
|
||||
"msr PSPLIM, r0\n\t"
|
||||
"ldr r0, =%0\n\t"
|
||||
"msr MSP, r0\n\t"
|
||||
:
|
||||
: "i" (STACK_TOP), "i" (STACK_LIMIT)
|
||||
: "r0"
|
||||
);
|
||||
}
|
||||
@@ -0,0 +1,126 @@
|
||||
/**
|
||||
******************************************************************************
|
||||
* @file rp2350_uart.c
|
||||
* @author Kevin Thomas
|
||||
* @brief UART0 driver implementation for RP2350.
|
||||
*
|
||||
* Configures UART0 on GPIO 0 (TX) and GPIO 1 (RX) at 115200
|
||||
* baud using the 12 MHz XOSC clock.
|
||||
*
|
||||
******************************************************************************
|
||||
* @attention
|
||||
*
|
||||
* Copyright (c) 2026 Kevin Thomas.
|
||||
* All rights reserved.
|
||||
*
|
||||
* This software is licensed under terms that can be found in the LICENSE file
|
||||
* in the root directory of this software component.
|
||||
* If no LICENSE file comes with this software, it is provided AS-IS.
|
||||
*
|
||||
******************************************************************************
|
||||
*/
|
||||
|
||||
#include "rp2350_uart.h"
|
||||
|
||||
#define UART_BASE ((volatile uint32_t *) UART0_BASE)
|
||||
|
||||
/**
|
||||
* @brief Clear the UART0 reset bit in the reset controller.
|
||||
* @retval None
|
||||
*/
|
||||
static void _uart_clear_reset_bit(void)
|
||||
{
|
||||
uint32_t value;
|
||||
value = RESETS->RESET;
|
||||
value &= ~(1U << RESETS_RESET_UART0_SHIFT);
|
||||
RESETS->RESET = value;
|
||||
}
|
||||
|
||||
/**
|
||||
* @brief Wait until the UART0 block is out of reset.
|
||||
* @retval None
|
||||
*/
|
||||
static void _uart_wait_reset_done(void)
|
||||
{
|
||||
while ((RESETS->RESET_DONE & (1U << RESETS_RESET_UART0_SHIFT)) == 0) {
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* @brief Configure GPIO pins 0 (TX) and 1 (RX) for UART function.
|
||||
* @retval None
|
||||
*/
|
||||
static void _uart_configure_pins(void)
|
||||
{
|
||||
IO_BANK0->GPIO[0].CTRL = IO_BANK0_CTRL_FUNCSEL_UART;
|
||||
IO_BANK0->GPIO[1].CTRL = IO_BANK0_CTRL_FUNCSEL_UART;
|
||||
PADS_BANK0->GPIO[0] = 0x04;
|
||||
PADS_BANK0->GPIO[1] = 0x40;
|
||||
}
|
||||
|
||||
/**
|
||||
* @brief Set UART0 baud rate divisors for 115200 at 12 MHz.
|
||||
* @retval None
|
||||
*/
|
||||
static void _uart_set_baud(void)
|
||||
{
|
||||
UART_BASE[UART_CR_OFFSET] = 0;
|
||||
UART_BASE[UART_IBRD_OFFSET] = 6;
|
||||
UART_BASE[UART_FBRD_OFFSET] = 33;
|
||||
}
|
||||
|
||||
/**
|
||||
* @brief Configure line control and enable UART0.
|
||||
* @retval None
|
||||
*/
|
||||
static void _uart_enable(void)
|
||||
{
|
||||
UART_BASE[UART_LCR_H_OFFSET] = UART_LCR_H_8N1_FIFO;
|
||||
UART_BASE[UART_CR_OFFSET] = UART_CR_ENABLE;
|
||||
}
|
||||
|
||||
void uart_release_reset(void)
|
||||
{
|
||||
_uart_clear_reset_bit();
|
||||
_uart_wait_reset_done();
|
||||
}
|
||||
|
||||
void uart_init(void)
|
||||
{
|
||||
_uart_configure_pins();
|
||||
_uart_set_baud();
|
||||
_uart_enable();
|
||||
}
|
||||
|
||||
bool uart_is_readable(void)
|
||||
{
|
||||
return (UART_BASE[UART_FR_OFFSET] & UART_FR_RXFE_MASK) == 0;
|
||||
}
|
||||
|
||||
char uart_getchar(void)
|
||||
{
|
||||
while (UART_BASE[UART_FR_OFFSET] & UART_FR_RXFE_MASK) {
|
||||
}
|
||||
return (char)(UART_BASE[UART_DR_OFFSET] & 0xFF);
|
||||
}
|
||||
|
||||
void uart_putchar(char c)
|
||||
{
|
||||
while (UART_BASE[UART_FR_OFFSET] & UART_FR_TXFF_MASK) {
|
||||
}
|
||||
UART_BASE[UART_DR_OFFSET] = (uint32_t)c;
|
||||
}
|
||||
|
||||
void uart_puts(const char *str)
|
||||
{
|
||||
while (*str) {
|
||||
uart_putchar(*str++);
|
||||
}
|
||||
}
|
||||
|
||||
char uart_to_upper(char c)
|
||||
{
|
||||
if (c >= 'a' && c <= 'z')
|
||||
return (char)(c - 32);
|
||||
return c;
|
||||
}
|
||||
@@ -0,0 +1,46 @@
|
||||
/**
|
||||
******************************************************************************
|
||||
* @file rp2350_xosc.c
|
||||
* @author Kevin Thomas
|
||||
* @brief XOSC driver implementation for RP2350.
|
||||
*
|
||||
* Configures the external crystal oscillator and enables the
|
||||
* peripheral clock sourced from XOSC.
|
||||
*
|
||||
******************************************************************************
|
||||
* @attention
|
||||
*
|
||||
* Copyright (c) 2026 Kevin Thomas.
|
||||
* All rights reserved.
|
||||
*
|
||||
* This software is licensed under terms that can be found in the LICENSE file
|
||||
* in the root directory of this software component.
|
||||
* If no LICENSE file comes with this software, it is provided AS-IS.
|
||||
*
|
||||
******************************************************************************
|
||||
*/
|
||||
|
||||
#include "rp2350_xosc.h"
|
||||
|
||||
void xosc_init(void)
|
||||
{
|
||||
XOSC->STARTUP = 0x00C4U;
|
||||
XOSC->CTRL = 0x00FABAA0U;
|
||||
while ((XOSC->STATUS & (1U << XOSC_STATUS_STABLE_SHIFT)) == 0) {
|
||||
}
|
||||
}
|
||||
|
||||
void xosc_enable_peri_clk(void)
|
||||
{
|
||||
uint32_t value;
|
||||
value = CLOCKS->CLK_PERI_CTRL;
|
||||
value &= ~CLK_PERI_CTRL_AUXSRC_MASK;
|
||||
value |= (1U << CLK_PERI_CTRL_ENABLE_SHIFT);
|
||||
value |= (CLK_PERI_CTRL_AUXSRC_XOSC << CLK_PERI_CTRL_AUXSRC_SHIFT);
|
||||
CLOCKS->CLK_PERI_CTRL = value;
|
||||
}
|
||||
|
||||
void xosc_set_clk_ref(void)
|
||||
{
|
||||
CLOCKS->CLK_REF_CTRL = CLK_REF_CTRL_SRC_XOSC;
|
||||
}
|
||||
@@ -0,0 +1,38 @@
|
||||
/**
|
||||
******************************************************************************
|
||||
* @file vector_table.c
|
||||
* @author Kevin Thomas
|
||||
* @brief Vector table with initial stack pointer and reset handler.
|
||||
*
|
||||
* Placed in the .vectors section at the start of flash.
|
||||
* The Thumb bit (bit 0 = 1) is automatically set by the
|
||||
* linker for function pointers in Thumb mode.
|
||||
*
|
||||
******************************************************************************
|
||||
* @attention
|
||||
*
|
||||
* Copyright (c) 2026 Kevin Thomas.
|
||||
* All rights reserved.
|
||||
*
|
||||
* This software is licensed under terms that can be found in the LICENSE file
|
||||
* in the root directory of this software component.
|
||||
* If no LICENSE file comes with this software, it is provided AS-IS.
|
||||
*
|
||||
******************************************************************************
|
||||
*/
|
||||
|
||||
#include <stdint.h>
|
||||
|
||||
extern uint32_t _stack_top;
|
||||
extern void Reset_Handler(void);
|
||||
|
||||
typedef void (*vector_func_t)(void);
|
||||
|
||||
/**
|
||||
* @brief Vector table placed in .vectors section
|
||||
*/
|
||||
__attribute__((section(".vectors"), used))
|
||||
const void *_vectors[2] = {
|
||||
&_stack_top,
|
||||
Reset_Handler
|
||||
};
|
||||
Reference in New Issue
Block a user