前言
XR806硬件上支持SPI,I2C等其他外设接口，且DDR和FLASH，满足常见应用场景的开发，适合开发者进行方案评估、DIY或小规模产品研发使用。本篇文章，将使用到I2C接口，去控制OLED屏幕的显示。
OLED屏幕规格: 0.96英寸 主控SSD1306 I2C接口 地址 0x3C
XR806外设：I2C1
创建工程
参考device/xradio/xr806/ohosdemo目录下的wlan_demo,
拷贝wlan_demo为xr806_oled,并同步修改ohosdemo和xr806_oled目录下的BUILD.gn。
主要修改如下：
1、device/xradio/xr806/ohosdemo/BUILD.gn
group("ohosdemo") {
deps = [
#"hello_demo:app_hello",
#"iot_peripheral:app_peripheral",
#"wlan_demo:app_WlanTest",
"xr806_oled:app_oled", #增加app_oled目标编译
]
}
2、device/xradio/xr806/ohosdemo/xr806_oled/BUILD.gn
static_library("app_oled") {
configs = []
sources = [
"main.c",
]
cflags = board_cflags
include_dirs = board_include_dirs
include_dirs += [
".",
"thirdparty/ssd1306/ssd1306",
"//utils/native/lite/include",
"//foundation/communication/wifi_lite/interfaces/wifiservice",
]
deps = [
"thirdparty/ssd1306/ssd1306:oled_ssd1306",
]
}
注意：
- static_library代表生成静态库（.a）文件，其中包含main.c的静态库必须是app_打头，如app_hello，否则虽然可以编译成功，但无法生效;
- ~~xr806_oled/BUILD.gn中静态库app_oled的命名，需要和ohosdemo/BUILD.gn中的一致；
- thirdparty/ssd1306/ssd1306:oled_ssd1306 为依赖的开源库
工程编译
创建工程后，如果非首次编译，执行以下命令便可以编译：
hb build
编译如果遇到以下错误：
[OHOS ERROR] /*
[OHOS ERROR] *
[OHOS ERROR] * Automatically generated file; DO NOT EDIT.
[OHOS ERROR] * XR806 SDK Configuration
[OHOS ERROR] *
[OHOS ERROR] */
[OHOS ERROR] /*
[OHOS ERROR] *
[OHOS ERROR] * Automatically generated file; DO NOT EDIT.
[OHOS ERROR] * XR806 SDK Configuration
[OHOS ERROR] *
[OHOS ERROR] */
[OHOS ERROR] {
[OHOS ERROR] "magic" : "AWIH",
[OHOS ERROR] "version" : "0.5",
[OHOS ERROR] "image" : {"max_size": "1532K"},
[OHOS ERROR] "section" :[
[OHOS ERROR] {"id": "0xa5ff5a00", "bin" :"boot_40M.bin", "cert": "null", "flash_offs": "0K", "sram_offs": "0x00230000", "ep": "0x00230101", "attr":"0x1"},
[OHOS ERROR] {"id": "0xa5fe5a01", "bin" :"app.bin", "cert": "null", "flash_offs": "32K", "sram_offs": "0x00201000", "ep": "0x00201101", "attr":"0x1"},
[OHOS ERROR] {"id": "0xa5fd5a02", "bin" :"app_xip.bin", "cert": "null", "flash_offs": "99K", "sram_offs": "0xffffffff", "ep": "0xffffffff", "attr":"0x2"},
[OHOS ERROR] {"id": "0xa5fa5a05", "bin" :"wlan_bl.bin", "cert": "null", "flash_offs": "1170K", "sram_offs": "0xffffffff", "ep": "0xffffffff", "attr":"0x1"},
[OHOS ERROR] {"id": "0xa5f95a06", "bin" :"wlan_fw.bin", "cert": "null", "flash_offs": "1173K", "sram_offs": "0xffffffff", "ep": "0xffffffff", "attr":"0x1"},
[OHOS ERROR] {"id": "0xa5f85a07", "bin" :"sys_sdd_40M.bin", "cert": "null", "flash_offs": "1198K", "sram_offs": "0xffffffff", "ep": "0xffffffff", "attr":"0x1"},
[OHOS ERROR] {}
[OHOS ERROR] ]
[OHOS ERROR] }
[OHOS ERROR]
[OHOS ERROR] make[2]: *** [../../../../project/project.mk:520：image] 错误 255
[OHOS ERROR] make[2]: 离开目录“/home/algo/openharmony/xr806/device/xradio/xr806/xr_skylark/project/demo/audio_demo/gcc”
[OHOS ERROR] make[1]: *** [../../../../project/project.mk:493：__build] 错误 2
[OHOS ERROR] make[1]: 离开目录“/home/algo/openharmony/xr806/device/xradio/xr806/xr_skylark/project/demo/audio_demo/gcc”
[OHOS ERROR] make: *** [Makefile:164：build] 错误 2
[OHOS ERROR] you can check build log in /home/algo/openharmony/xr806/out/xr806/wifi_skylark/build.log
[OHOS ERROR] /home/algo/.local/bin/ninja -w dupbuild=warn -C /home/algo/openharmony/xr806/out/xr806/wifi_skylark failed, return code is 1
执行以下命令后，再次编译即可：
cp device/xradio/xr806/xr_skylark/project/demo/audio_demo/image/xr806/image_auto_cal.cfg device/xradio/xr806/xr_skylark/project/demo/audio_demo/image/xr806/image.cfg
编译后生成的镜像，便可以烧录验证。
注：以上基础工程是基于wlan_demo，oled屏幕显示需要使用I2C外设和移植oled库
库移植
其实XR806本身自带了OLED主控为SSD1306的驱动（采用的是SPI接口方式），移植基于I2C接口的库也相对简单，可以参考开源库harmonyos-ssd1306，将其中的I2C相关头文件和API替换为XR806 OpenHarmony中的相关头文件和API，编译通过即可。
其中涉及到BUID.gn的修改如下：
static_library("oled_ssd1306") {
sources = [
"ssd1306.c",
"ssd1306_fonts.c",
]
include_dirs = [
".",
"//kernel/liteos_m/kernel/arch/include",
"//utils/native/lite/include",
"//base/iot_hardware/peripheral/interfaces/kits",
]
}
开源库主要修改如下：
#include "iot_i2c.h"
#include "iot_errno.h"
/**
* @brief Defines I2C data transmission attributes.
*/
typedef struct {
/** Pointer to the buffer storing data to send */
unsigned char *sendBuf;
/** Length of data to send */
unsigned int sendLen;
/** Pointer to the buffer for storing data to receive */
unsigned char *receiveBuf;
/** Length of data received */
unsigned int receiveLen;
} IotI2cData;
static uint32_t ssd1306_SendData(uint8_t* data, size_t size)
{
uint32_t id = SSD1306_I2C_IDX;
IotI2cData i2cData = {0};
i2cData.sendBuf = data;
i2cData.sendLen = size;
return IoTI2cWrite(id, SSD1306_I2C_ADDR, i2cData.sendBuf, i2cData.sendLen);
}
ssd1306.h头文件定义SSD1306_I2C_IDX为1
显示程序
程序部分参考了上面提到的OLED库，完整的测试程序，可以参考harmonyos-ssd1306里的example.
/*
* Copyright (c) 2021-2031, AlgoIdeas
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2020-12-13 AlgoIdeas the first version
*/
#include <stdio.h>
#include "ohos_init.h"
#include "kernel/os/os.h"
#include "ssd1306.h"
#define OLED_I2C_BAUDRATE 100000
static OS_Thread_t g_main_thread;
static void DrawChinese(void)
{
const uint32_t W = 12, H = 12, S = 16;
uint8_t fonts[][24] = {
{
/*-- ID:0,字符:"您",ASCII编码:C4FA,对应字:宽x高=12x12,画布:宽W=16 高H=12,共24字节*/
0x14,0x00,0x24,0x00,0x2F,0xF0,0x71,0x20,0xA5,0x40,0x29,0x20,0x33,0x10,0x20,0x00,
0x54,0x40,0x52,0xA0,0x90,0x90,0x0F,0x80,
},{
/*-- ID:1,字符:"好",ASCII编码:BAC3,对应字:宽x高=12x12,画布:宽W=16 高H=12,共24字节*/
0x20,0x00,0x27,0xE0,0x20,0x40,0xF8,0x80,0x48,0x80,0x48,0xA0,0x57,0xF0,0x50,0x80,
0x30,0x80,0x28,0x80,0x4A,0x80,0x81,0x00,
},{
/*-- ID:2,字符:"鸿",ASCII编码:BAE8,对应字:宽x高=12x12,画布:宽W=16 高H=12,共24字节*/
0x00,0x40,0x80,0x80,0x5D,0xE0,0x09,0x20,0xC9,0xA0,0x09,0x60,0x29,0x00,0xCD,0xF0,
0x58,0x10,0x43,0xD0,0x40,0x10,0x40,0x60,
},{
/*-- ID:3,字符:"蒙",ASCII编码:C3C9,对应字:宽x高=12x12,画布:宽W=16 高H=12,共24字节*/
0x09,0x00,0x7F,0xE0,0x09,0x00,0x7F,0xF0,0x80,0x10,0x7F,0xE0,0x0C,0x40,0x32,0x80,
0xC7,0x00,0x0A,0x80,0x32,0x70,0xC6,0x20
}
};
ssd1306_Fill(Black);
for (size_t i = 0; i < sizeof(fonts)/sizeof(fonts[0]); i++) {
ssd1306_DrawRegion(i * H + 32, 26, W, H, fonts[i], sizeof(fonts[0]), S);
}
ssd1306_UpdateScreen();
sleep(1);
}
static void MainThread(void *arg)
{
IoTI2cInit(SSD1306_I2C_IDX, OLED_I2C_BAUDRATE);
usleep(20*1000);
printf("ssd1306_Init.\n");
ssd1306_Init();
ssd1306_Fill(Black);
ssd1306_SetCursor(22, 27);
ssd1306_DrawString("Hello XR806!", Font_7x10, White);
uint32_t start = HAL_GetTick();
ssd1306_UpdateScreen();
uint32_t end = HAL_GetTick();
printf("ssd1306_UpdateScreen, time cost: %d ms.\n", end - start);
usleep(2000*1000);
while (1) {
DrawChinese();
}
}
void OledMain(void)
{
if (OS_ThreadCreate(&g_main_thread, "MainThread", MainThread, NULL,
OS_THREAD_PRIO_APP, 4 * 1024) != OS_OK) {
printf("[ERR] Create MainThread Failed\n");
}
}
SYS_RUN(OledMain);
运行效果
最终OLED显示：您好鸿蒙
参考资料
【XR806开发板试用】系列之一 - Linux环境下Ubuntu完全开发流程
https://xr806.docs.aw-ol.com/
https://aijishu.com/a/1060000000256653
本贴转自极术社区：https://aijishu.com/a/1060000000284333
作者：H2O2_H2O2
