Developing with 新唐科技(Nuvoton)'s ARM Cortex-M Development Board

tags: `Nuvoton`, `NUC472`, `Cortex-M4`, `MCU`, `arm-none-eabi-gcc`

Development Environment

My host is an Arch Linux (x86_64) system. The target chip is an ARM Cortex-M4 MCU. Therefore, install the arm-none-eabi- toolchain packages:
- arm-none-eabi-binutils
- arm-none-eabi-gcc
- arm-none-eabi-newlib
- arm-none-eabi-gdb
I prefer the Makefile tool. So, make is installed, too.
Also, need OpenOCD to flash and debug.
- Upstream OpenOCD must includes these commits at least:
  - flash/nor/numicro: reorder the parts list
  - flash: support Nuvoton M541 & NUC442/472 series
  - tcl: add a configuration file for Nuvoton M541 & NUC442/472 series
    The commits have been merged into the master branch.
- Or, downstream Nuvoton OpenOCD

Developing with NuTiny-SDK-NUC472

NuTiny-SDK-NUC472 User Manual
The MCU is Nuvoton NUC472HI8AE
- However, Nuvoton marks it as Not Recommended For New Designs (NRND)
- Recommended Part Number: M487 Ethernet Series
- I still write this record, because the development board NuTiny-SDK-NUC472 is much cheaper then others. If someone give me the newer board (Cortex-M4), I may write another article for it.
Nuvoton has provided the NUC472/442 BSP at https://github.com/OpenNuvoton/NUC472_442BSP, which follows Common Microcontroller Software Interface Standard (CMSIS).

Use the NUC472-NuTiny's LED Sample as the Example


$ git clone https://github.com/OpenNuvoton/NUC472_442BSP
$ cd NUC472_442BSP/SampleCode/NUC472-NuTiny/LED/

Add the Makefile into the LED sample code directory.







[LED]$ ls -l
total 20
drwxr-xr-x 2 zack zack 4096 Oct 22 14:32 GCC
drwxr-xr-x 2 zack zack 4096 Oct 22 14:32 IAR
drwxr-xr-x 2 zack zack 4096 Oct 22 14:32 KEIL
-rw-r--r-- 1 zack zack 3420 Oct 22 14:32 main.c
-rw-r--r-- 1 zack zack 3090 Oct 22 15:05 Makefile

PS. If it is downstream Nuvoton OpenOCD, the TARGETCHIP in the Makefile should be set as "target/numicroM4.cfg".

Build the LED application with make:





[LED]$ make
arm-none-eabi-gcc -I../../../../NUC472_442BSP/Library/CMSIS/Include -I../../../../NUC472_442BSP/Library/StdDriver/inc -I../../../../NUC472_442BSP/Library/Device/Nuvoton/NUC472_442/Include -I.  -ggdb -Os -Wall -Wextra -Warray-bounds -mlittle-endian -mthumb -mcpu=cortex-m4 -mthumb-interwork -mfloat-abi=hard -mfpu=fpv4-sp-d16 -T../../../../NUC472_442BSP/Library/Device/Nuvoton/NUC472_442/Source/GCC/gcc_arm.ld main.c ../../../../NUC472_442BSP/Library/StdDriver/src/clk.c ../../../../NUC472_442BSP/Library/StdDriver/src/gpio.c ../../../../NUC472_442BSP/Library/StdDriver/src/sys.c ../../../../NUC472_442BSP/Library/Device/Nuvoton/NUC472_442/Source/system_NUC472_442.c ../../../../NUC472_442BSP/Library/Device/Nuvoton/NUC472_442/Source/GCC/startup_NUC472_442.S -o LED.elf
...
arm-none-eabi-objcopy -O ihex LED.elf   LED.hex
arm-none-eabi-objcopy -O binary LED.elf LED.bin

Connect the NuTiny-SDK-NUC472 to your host via the USB cable.

Flash the built image into NuTiny-SDK-NUC472 with make flash:

$ make flash
openocd -f "interface/nulink.cfg" -f "target/numicro_m4.cfg" \
        -c "program LED.elf verify reset exit"
Open On-Chip Debugger 0.12.0-rc2+dev-00007-gdc1e6d4d4 (2022-11-13-14:48)
Licensed under GNU GPL v2
For bug reports, read
        http://openocd.org/doc/doxygen/bugs.html
hla_swd
Info : The selected transport took over low-level target control. The results might differ compared to plain JTAG/SWD
Info : clock speed 1000 kHz
Info : Nu-Link firmware_version 6535, product_id (0x00012009)
Info : Adapter is Nu-Link
Info : IDCODE: 0x2BA01477
Info : [NuMicro.cpu] Cortex-M4 r0p1 processor detected
Info : [NuMicro.cpu] target has 6 breakpoints, 4 watchpoints
Info : starting gdb server for NuMicro.cpu on 3333
Info : Listening on port 3333 for gdb connections
[NuMicro.cpu] halted due to breakpoint, current mode: Thread 
xPSR: 0x01000000 pc: 0x00000f5c msp: 0x20010000
[NuMicro.cpu] halted due to debug-request, current mode: Thread 
xPSR: 0x01000000 pc: 0x00000f5c msp: 0x20010000
** Programming Started **
Info : Device ID: 0x00047201
Info : Device Name: NUC472HI8AE
Info : bank base = 0x00000000, size = 0x00080000
Warn : Adding extra erase range, 0x00001770 .. 0x000017ff
Info : Nuvoton NuMicro: Sector Erase ... (0 to 2)
Info : Nuvoton NuMicro: Flash Write ...
** Programming Finished **
** Verify Started **
** Verified OK **
** Resetting Target **
shutdown command invoked

After flash, the onboard LED should become blinking.

CMSIS, Standard and Device Libraries for the Makefile

NUC472/442 BSP provides the libraries:

CMSIS library is under path Library/CMSIS.
Standard library is under path Library/StdDriver.
NUC472/442's library is under path Library/Device/Nuvoton/NUC472_442.
NUC472/442's system clock initialization is at Library/Device/Nuvoton/NUC472_442/Source/system_NUC472_442.c.
NUC472/442's startup file is at Library/Device/Nuvoton/NUC472_442/Source/GCC/startup_NUC472_442.S.
NUC472/442's linker file is at Library/Device/Nuvoton/NUC472_442/Source/GCC/gcc_arm.ld.

Debugging

Debug with GDB via OpenOCD and Nu-Link.

Start the gdb server with Nu-Link and the numicro M4 configs:

$ openocd -f "interface/nulink.cfg" -f "target/numicro_m4.cfg"
Open On-Chip Debugger 0.12.0-rc2+dev-00007-gdc1e6d4d4 (2022-11-13-14:48)
Licensed under GNU GPL v2
For bug reports, read
        http://openocd.org/doc/doxygen/bugs.html
hla_swd
Info : The selected transport took over low-level target control. The results might differ compared to plain JTAG/SWD
Info : Listening on port 6666 for tcl connections
Info : Listening on port 4444 for telnet connections
Info : clock speed 1000 kHz
Info : Nu-Link firmware_version 6535, product_id (0x00012009)
Info : Adapter is Nu-Link
Info : IDCODE: 0x2BA01477
Info : [NuMicro.cpu] Cortex-M4 r0p1 processor detected
Info : [NuMicro.cpu] target has 6 breakpoints, 4 watchpoints
Info : starting gdb server for NuMicro.cpu on 3333
Info : Listening on port 3333 for gdb connections
[NuMicro.cpu] halted due to breakpoint, current mode: Thread 
xPSR: 0x01000000 pc: 0x00000f5c msp: 0x20010000

It shows that the gdb server is listening on port 3333.

Have the gdb client connecting to the gdb server to debug the LED.elf flashed on the MCU chip Nuvoton NUC472HI8AE:
















































$ arm-none-eabi-gdb LED.elf 
GNU gdb (GDB) 12.1
...
Reading symbols from LED.elf...
(gdb) target remote localhost:3333
Remote debugging using localhost:3333
warning: Overlapping regions in memory map: ignoring
Reset_Handler () at ../../../../NUC472_442BSP/Library/Device/Nuvoton/NUC472_442/Source/GCC/startup_NUC472_442.S:268
268		ldr	r1, =__etext
(gdb) hbreak main.c:86
Hardware assisted breakpoint 1 at 0x3a2: file main.c, line 86.
(gdb) continue
Continuing.

Breakpoint 1, main () at main.c:86
86	        PB10 = 0;
(gdb) list
81	    /* Configure PB.10 as Output mode */
82	    GPIO_SetMode(PB, BIT10, GPIO_MODE_OUTPUT);
83	
84	    while(1)
85	    {
86	        PB10 = 0;
87	        CLK_SysTickDelay(500000);
88	        PB10 = 1;
89	        CLK_SysTickDelay(500000);
90	    }
(gdb) hbreak 88
Hardware assisted breakpoint 2 at 0x3ae: file main.c, line 88.
(gdb) continue
Continuing.
halted: PC: 0x000003a4

Breakpoint 2, main () at main.c:88
88	        PB10 = 1;
(gdb) continue
Continuing.
halted: PC: 0x000003b0

Breakpoint 1, main () at main.c:86
86	        PB10 = 0;
(gdb) continue
Continuing.
halted: PC: 0x000003a4

Breakpoint 2, main () at main.c:88
88	        PB10 = 1;
(gdb)

Use hbreak (hardware-assisted breakpoint) to add a break point, instead of break.
Reference: 5.1.1 Setting Breakpoints

Developing with 新唐科技(Nuvoton)'s ARM Cortex-M Development Board

tags: Nuvoton, NUC472, Cortex-M4, MCU, arm-none-eabi-gcc

Development Environment

Developing with NuTiny-SDK-NUC472

Use the NUC472-NuTiny's LED Sample as the Example

CMSIS, Standard and Device Libraries for the Makefile

Debugging

Reference

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tags: `Nuvoton`, `NUC472`, `Cortex-M4`, `MCU`, `arm-none-eabi-gcc`