Using Sipeed TANG PriMER [2] – RISC-V development with Arduino IDE

In the previous article, we have set up the environment of the TANG PriMER FPGA development board from SiPeed, and have confirmed the logic synthesis and writing of the samples.

Bluish-purple tech

Trying Sipeed TANG PriMER [1] - Setting up the development environment

https://mytoolbox.tech/tec/en/2022/01/04/sipeed_tang_primer_setup_e/

I got a TANG PriMER FPGA development board from SiPeed in China. This page describes the setup and usage of the environment.Sipeed TANG PriMER FPGA Development BoardThe Sipeed TANG PriMER FPGA Development Board is a small FPGA development board equipped with an Anlogic EG4S20 FPGA, supporting the Hummingbird RISC-V softcore.The main hardware specifications are as follows- FPGA: EG4S20BG256 Logic unit: 20K (LUT4/LUT5 hybrid architecture)- SRAM: approx. 130KB- SDRAM: 64Mb- Flash: FPGA configur...

In this article, we will start to synthesize the RISC-V processor, write it to the FPGA, build the software using Arduino IDE, and write it to the ROM on the board.

Logic Synthesis of RISC-V E203 Core and Writing to FPGA

The first step is to synthesize the RISC-V core (Tang_E203_Mini). Download the necessary files from the following link.

https://github.com/riktw/Tang_E203_Mini

Launch the FPGA development environment TD, open the project file e203egmini_new.al from the Open Project menu, and execute the logic synthesis by clicking Process → Run.

Setting up the software development environment

Next, let’s set up the RISC-V software development environment. This time, we will build software with Arduino IDE and write to Flash using RV debugger and OpenOCD. Therefore, you need to rebuild OpenOCD.

Downloading and setting up the Arduino IDE

Download and install the Arduino IDE from the official website below.

https://www.arduino.cc/en/software

Start the Arduino IDE and add the following URL to the board manager URL in File → Preferences.

https://bigbits.oss-cn-qingdao.aliyuncs.com/Arduino_for_Licheetang_with_hbird_e203_mini/v0_1/package_licheetang_index.json

Next, select the LicheeTang Hbird E203 Board from Tools → Board → Board Manager. Also, select LicheeTang OpenOCD in Tools → Write Device.

Setting up the build environment for Open OCD

As mentioned above, we need to rebuild OpenOCD, so we need to set up the build environment (minGW). Get the installer from the following official site and install it.

http://www.msys2.org/

After the installation is complete, start MSYS2 MinGW x64 and use the following commands to update the package database.

pacman -Sy

Next, upgrade the packages.

pacman -Su

The next step is to install the development environment (GCC) and other tools required for development.

pacman -S mingw-w64-x86_64-toolchain

pacman -S mingw-w64-x86_64-libusb

pacman -S make autoconf automake

pacman -S libtool mingw-w64-x86_64-libftdi git

Obtaining and building the openocd source for LicheeTang

Now that the setup of the development environment has been completed, we will obtain the openocd source and build it. Create an appropriate directory for development, and execute the following command in the directory to obtain the openocd source for LicheeTang.

git clone https://github.com/Lichee-Pi/LicheeTang_openocd.git

After downloading, go to the directory of the source you obtained and execute the following command.

./bootstrap

CFLAGS=-D_FTDI_DISABLE_DEPRECATED CFLAGS=-Wno-stringop-overflow ./configure

Next, let’s make. In my environment, a build error occurred during the above make, so I made some modifications to the source code and passed the build.

make

Once the build is complete, a new openocd.exe will be created under /src. Copy (replace) this and libftdi1.dll under mingw64/bin to the ArduinoIDE folder (C:\ Users\AppData\AppData\Local\Arduino15\a1\bin). Copy (replace) it to the ArduinoIDE folder (C:\licheetang\tools\openocd\a1\bin).
You are now ready to use the ArduinoIDE to develop software for the LicheeTang RISC-V (E203).

Connection between RV Debugger and TANG PriMER board

Connect JTAG / UART between RV debugger for writing programs and TANG PriMER board. Corresponding pins are as follows.

Lichee Tang Pin	RV
H13 (U0_Tx)	Tx
J13 (U0_Rx)	Rx
C9 (TMS)	TMS
B6 (TDI)	TDI
C5 (TCK)	TCK
A4 (TDO)	TDO
G (GND)	GND

Creating and Writing Programs

Create and write the following program on the ArduinoIDE.

#define LED_RED 9
#define LED_BLUE 10
#define LED_GREEN 11
#define DELAY_TIME 100

void setup()
{
  Serial.begin(9600);

pinMode(LED_RED, OUTPUT);
  pinMode(LED_BLUE, OUTPUT);
  pinMode(LED_GREEN, OUTPUT);
  digitalWrite(LED_RED, HIGH);
  digitalWrite(LED_BLUE, HIGH);
  digitalWrite(LED_GREEN, HIGH);
  Serial.println("===== Blink Test =====");
}

void loop()
{
  digitalWrite(LED_RED, LOW);
  Serial.println("RED : ON");
  delay(DELAY_TIME);
  digitalWrite(LED_RED, HIGH);
  Serial.println("RED : OFF");
  delay(DELAY_TIME);
  digitalWrite(LED_BLUE, LOW);
  Serial.println("BLUE : ON");
  delay(DELAY_TIME);
  digitalWrite(LED_BLUE, HIGH);
  Serial.println("BLUE : OFF");
  delay(DELAY_TIME);
  digitalWrite(LED_GREEN, LOW);
  Serial.println("GREEN : ON");
  delay(DELAY_TIME);
  digitalWrite(LED_GREEN, HIGH); 
  Serial.println("GREEN : OFF");
  delay(DELAY_TIME);
}

If the full-color LED on the board lights up red → blue → green every 100 ms, the writing is successful.

References

I used the following as a reference.
http://galaxystar.image.coocan.jp/tangprimer.htm

https://ameblo.jp/takeoka/entry-12607107193.html

https://qiita.com/Nanchite4618/items/62ff04e3345519b3a939

https://blog.csdn.net/u013507936/article/details/86737964