Eclipse ThreadX SD-card boot-sector dump on the EK-RA8D2. More...

#include <stddef.h>
#include <stdint.h>
#include "ra8_attributes.h"
#include "ra8_board_ek_ra8d2.h"
#include "ra8_boot_entry.h"
#include "ra8_cgc.h"
#include "ra8_err.h"
#include "ra8_isr.h"
#include "ra8_sdcard.h"
#include "ra8_threadx.h"
#include "tx_api.h"

Include dependency graph for main.c:

Enumerations
enum	sdcard_stack_t : uint16_t { k_sdcard_thread_stack_bytes = 4096U }
	Stack size, in bytes, for the SD card thread. More...
enum	sdcard_priority_t : uint8_t { k_sdcard_thread_priority = 4U }
	Thread priority for the SD card thread. More...
enum	sdcard_baud_t : uint32_t { k_sdcard_console_baud = 115200U }
	Console baud (115200 8N1). More...
enum	sdcard_period_t : uint16_t { k_sdcard_loop_ticks = 5000U }
	Loop period in ThreadX ticks (port/threadx/inc/tx_user.h pins to 1 ms). More...
enum	sdcard_layout_t : uint8_t { k_sdcard_sdhi_instance = 0U , k_sdcard_dump_bytes = 16U }
	SDHI pin layout constants. More...
enum	sdcard_hex_t : uint8_t { k_sdcard_hex_chars_per_byte = 3U , k_sdcard_hex_nibble_shift = 4U , k_sdcard_hex_nibble_mask = 0x0FU , k_sdcard_hex_alpha_threshold = 10U }
	ASCII-hex formatting constants. More...
enum	sdcard_block_size_t : uint16_t { k_sdcard_block_bytes = 512U }
	SD logical block size (512 bytes for SDHC/SDXC). More...

Functions
void	_tx_timer_interrupt (void)
void	SysTick_Handler (void)
	SysTick exception handler – tail-calls the ThreadX timer.
static char	internal_sdcard_nibble_to_hex (uint8_t nibble)
	Convert a single nibble to its ASCII hex character.
static void	internal_sdcard_hex_dump (const uint8_t in, uint8_t len, char out)
	Format len bytes from in into "XX XX ..." ASCII.
static void	internal_sdcard_log (const char *s)
	Push a NUL-terminated ASCII string out the J-Link OB VCOM.
static void	internal_sdcard_one_pass (void)
	Read sector 0 into s_sdcard_block and log status / hex dump.
static void	internal_sdcard_thread_entry (ULONG thread_input)
	Thread entry: init the card once, then loop reading sector 0.
void	tx_application_define (void *first_unused_memory)
	ThreadX application initialisation callback.
void	main (void)
	Application entry.

Variables
static uint8_t	s_sdcard_stack [k_sdcard_thread_stack_bytes]
	Stack for the SD card thread (32-bit aligned per ARMv8-M AAPCS).
static TX_THREAD	s_sdcard_thread
	Thread control block.
static uint8_t	s_sdcard_block [k_sdcard_block_bytes]
	Block buffer for one SD sector.

Detailed Description

Eclipse ThreadX SD-card boot-sector dump on the EK-RA8D2.

Tag: [Ring 6 / APP] {World: S}

One ThreadX thread that exercises the full ra8_sdcard HAL stack:

Route the eight SDHI pins (CMD, CLK, DAT0..3, WP, CD) on port 4 to the SDHI peripheral function via ra8_board_sdhi_pins_init.
Bring the J-Link OB VCOM console up at 115200 8N1 via ra8_board_uart_console_init.
ra8_sdcard_init runs the standard SD Physical Layer initialization sequence (CMD0 -> CMD7) on SDHI instance 0.
ra8_sdcard_read_blocks(0, ...) reads sector 0 (the MBR / boot sector) into a 512-byte SRAM buffer.
The first 16 bytes are formatted as ASCII hex (XX XX XX XX...) and pushed out the console; LED1 toggles once per pass to make the activity visible.

SDHI pin map is owned by the BSP (ra8_board_sdhi_pins_init): port 4, pins 0..7 routed to the on-chip SDHI block.

Threads

Name	Priority	Period	Action
sdcard	4	5000 ms loop	Read block 0, dump 16 bytes

Copyright: Copyright (c) 2026 Brighton Sikarskie SPDX-License-Identifier: MIT

Since: 0.1.0

Definition in file main.c.

Enumeration Type Documentation

◆ sdcard_baud_t

enum sdcard_baud_t : uint32_t

Console baud (115200 8N1).

Enumerator
k_sdcard_console_baud	Sdcard console baud.

Definition at line 79 of file main.c.

◆ sdcard_block_size_t

enum sdcard_block_size_t : uint16_t

SD logical block size (512 bytes for SDHC/SDXC).

Enumerator
k_sdcard_block_bytes	Sdcard block bytes.

Definition at line 111 of file main.c.

◆ sdcard_hex_t

enum sdcard_hex_t : uint8_t

ASCII-hex formatting constants.

Enumerator
k_sdcard_hex_chars_per_byte	"XX " incl. trailing space.
k_sdcard_hex_nibble_shift	High-nibble right-shift.
k_sdcard_hex_nibble_mask	Low-nibble mask.
k_sdcard_hex_alpha_threshold	10..15 -> 'A'..'F'.

Definition at line 101 of file main.c.

◆ sdcard_layout_t

enum sdcard_layout_t : uint8_t

SDHI pin layout constants.

Enumerator
k_sdcard_sdhi_instance	SDHI instance index.
k_sdcard_dump_bytes	Bytes from sector 0 to print.

Definition at line 93 of file main.c.

◆ sdcard_period_t

enum sdcard_period_t : uint16_t

Loop period in ThreadX ticks (port/threadx/inc/tx_user.h pins to 1 ms).

Enumerator
k_sdcard_loop_ticks	Sdcard loop ticks.

Definition at line 86 of file main.c.

◆ sdcard_priority_t

enum sdcard_priority_t : uint8_t

Thread priority for the SD card thread.

Enumerator
k_sdcard_thread_priority	Sdcard thread priority.

Definition at line 72 of file main.c.

◆ sdcard_stack_t

enum sdcard_stack_t : uint16_t

Stack size, in bytes, for the SD card thread.

Enumerator
k_sdcard_thread_stack_bytes	Sdcard thread stack bytes.

Definition at line 65 of file main.c.

Function Documentation

◆ _tx_timer_interrupt()

void _tx_timer_interrupt ( void )

extern

Referenced by SysTick_Handler().

◆ internal_sdcard_hex_dump()

void internal_sdcard_hex_dump	(	const uint8_t *	in,
		uint8_t	len,
		char *	out )

static

Format len bytes from in into "XX XX ..." ASCII.

Expands each source byte to two uppercase hex digits followed by a space, using no terminator so the caller controls final framing.

Parameters

[in]	in	Source buffer.
[in]	len	Number of source bytes to format.
[out]	out	Destination buffer; must hold len * 3 bytes.

Precondition: in / out non-NULL; out has space for len * 3 bytes.; Source and destination spans do not overlap.

Postcondition: out holds an ASCII hex dump (no NUL terminator written).; Exactly len * 3 destination bytes are written.

Note: The caller appends the NUL terminator used by console logging.

Since: 0.1.0

Definition at line 196 of file main.c.

References internal_sdcard_nibble_to_hex(), k_sdcard_hex_chars_per_byte, k_sdcard_hex_nibble_mask, k_sdcard_hex_nibble_shift, and RA8_INTERNAL.

Referenced by internal_sdcard_one_pass().

◆ internal_sdcard_log()

void internal_sdcard_log ( const char * s )

static

Push a NUL-terminated ASCII string out the J-Link OB VCOM.

Measures a non-NULL string and submits exactly the payload bytes to the BSP console without heap allocation.

Parameters

[in] s NUL-terminated string. NULL is a no-op.

Precondition: ra8_board_uart_console_init has succeeded.; A non-NULL s denotes a readable NUL-terminated string.

Postcondition: Bytes have been handed to SCI3 TDR (or silently dropped on err).; NULL input returns without accessing the console.

Note: Diagnostic write errors do not stop the periodic card read loop.

Since: 0.1.0

Definition at line 222 of file main.c.

References ra8_board_uart_console_write(), and RA8_INTERNAL.

Referenced by internal_sdcard_one_pass(), and internal_sdcard_thread_entry().

◆ internal_sdcard_nibble_to_hex()

char internal_sdcard_nibble_to_hex ( uint8_t nibble )

static

Convert a single nibble to its ASCII hex character.

Masks the input to four bits, then maps the value through the numeric or uppercase alphabetic ASCII range.

Parameters

[in] nibble Low 4 bits of an arbitrary uint8_t.

Returns: ASCII char in '0'..'9' or 'A'..'F'.

Return values

'0'..'9'	Numeric hexadecimal digit.
'A'..'F'	Alphabetic hexadecimal digit.

Precondition: 0 <= nibble <= 15.; The execution character set uses contiguous decimal and A-F digits.

Postcondition: Returned byte is a printable ASCII hex digit.; No file-scope or caller-owned state is modified.

Note: Inputs above 15 are deterministically reduced to their low nibble.

Since: 0.1.0

Definition at line 171 of file main.c.

References k_sdcard_hex_alpha_threshold, k_sdcard_hex_nibble_mask, and RA8_INTERNAL.

Referenced by internal_sdcard_hex_dump().

◆ internal_sdcard_one_pass()

void internal_sdcard_one_pass ( void )

static

Read sector 0 into s_sdcard_block and log status / hex dump.

Performs one block read, formats the first fixed-size prefix on the stack, and emits either the formatted prefix or an error line.

Precondition: ra8_sdcard_init has succeeded.; The worker thread exclusively owns s_sdcard_block.

Postcondition: Either the dump line has been emitted or an error line has.; At most one sector is read during this invocation.

Note: Read failure is recoverable; the outer loop retries after its delay.

Since: 0.1.0

Definition at line 250 of file main.c.

References internal_sdcard_hex_dump(), internal_sdcard_log(), k_ra8_ok, k_sdcard_dump_bytes, k_sdcard_hex_chars_per_byte, RA8_INTERNAL, ra8_sdcard_read_blocks(), and s_sdcard_block.

Referenced by internal_sdcard_thread_entry().

◆ internal_sdcard_thread_entry()

void internal_sdcard_thread_entry ( ULONG thread_input )

static

Thread entry: init the card once, then loop reading sector 0.

Initializes the fixed SDHI instance and, on success, performs a read/log/LED/sleep cycle forever; failed initialization sleeps without I/O.

Parameters

[in] thread_input Unused (ThreadX cookie).

Precondition: Pins routed; console initialized; ThreadX scheduler running.; The static worker stack and sector buffer are exclusively assigned here.

Postcondition: Loops forever: read + dump + LED1 toggle + sleep.; The ThreadX input cookie is not interpreted or modified.

Note: Initialization failure is intentionally non-busy and waits each cycle.

Since: 0.1.0

Definition at line 279 of file main.c.

References internal_sdcard_log(), internal_sdcard_one_pass(), k_ra8_board_led1, k_ra8_ok, k_sdcard_loop_ticks, k_sdcard_sdhi_instance, ra8_board_led_toggle(), RA8_INTERNAL, ra8_sdcard_init(), and tx_thread_sleep.

Referenced by tx_application_define().

◆ main()

void main ( void )

Application entry.

The application entry point Reset_Handler hands control to.

Brings up LED, console, SDHI pins, then ThreadX.

Precondition: Reset_Handler has copied .data + zeroed .bss.; SystemInit has set VTOR, FPU, and priority grouping.

Postcondition: CPUCLK0 is raised to the PLL1 target before the kernel starts.; On clean entry the SD card thread runs forever.; On any HAL init failure the function halts in __WFI.

Since: 0.1.0

Definition at line 364 of file main.c.

References k_ra8_board_led1, k_ra8_ok, k_sdcard_console_baud, ra8_board_led_init(), ra8_board_sdhi_pins_init(), ra8_board_uart_console_init(), ra8_cgc_init(), and ra8_isr_globals_enable().

◆ SysTick_Handler()

void SysTick_Handler ( void )

SysTick exception handler – tail-calls the ThreadX timer.

Service one SysTick event for the core timebase.

Service the SysTick exception selected by the linked application.

Precondition: Called from exception context (IPSR == 15).; _tx_initialize_low_level has programmed SysTick.

Postcondition: One ThreadX tick elapsed; PendSV may be pending.

Definition at line 146 of file main.c.

References _tx_timer_interrupt().

◆ tx_application_define()

void tx_application_define ( void * first_unused_memory )

ThreadX application initialisation callback.

Parameters

[in] first_unused_memory Unused – the demo uses a static stack.

Precondition: Called from _tx_initialize_kernel_enter with IRQs masked.

Postcondition: SysTick is retuned to the live CPUCLK0 before scheduling starts.; The SD card thread is created and auto-started.

Definition at line 313 of file main.c.

References internal_sdcard_thread_entry(), k_ra8_ok, k_sdcard_thread_priority, k_sdcard_thread_stack_bytes, ra8_threadx_systick_retune(), s_sdcard_stack, s_sdcard_thread, s_thread_name, TX_AUTO_START, TX_NO_TIME_SLICE, TX_SUCCESS, and tx_thread_create.

Variable Documentation

◆ s_sdcard_block

uint8_t s_sdcard_block[k_sdcard_block_bytes]

static

Block buffer for one SD sector.

File-scope so it does not eat thread-stack budget.

Definition at line 136 of file main.c.

Referenced by internal_sdcard_one_pass().

◆ s_sdcard_stack

uint8_t s_sdcard_stack[k_sdcard_thread_stack_bytes]

static

Stack for the SD card thread (32-bit aligned per ARMv8-M AAPCS).

Definition at line 125 of file main.c.

Referenced by tx_application_define().

◆ s_sdcard_thread

TX_THREAD s_sdcard_thread

static

Thread control block.

ThreadX zeroes it on tx_thread_create.

Definition at line 130 of file main.c.

Referenced by tx_application_define().

Enumerations

Functions

Variables

Detailed Description

Enumeration Type Documentation

◆ sdcard_baud_t

◆ sdcard_block_size_t

◆ sdcard_hex_t

◆ sdcard_layout_t

◆ sdcard_period_t

◆ sdcard_priority_t

◆ sdcard_stack_t

Function Documentation

◆ _tx_timer_interrupt()

◆ internal_sdcard_hex_dump()

◆ internal_sdcard_log()

◆ internal_sdcard_nibble_to_hex()

◆ internal_sdcard_one_pass()

◆ internal_sdcard_thread_entry()

◆ main()

◆ SysTick_Handler()

◆ tx_application_define()

Variable Documentation

◆ s_sdcard_block

◆ s_sdcard_stack

◆ s_sdcard_thread