Search found 7 matches

by wulin76
Tue Jan 31, 2023 12:53 pm
Forum: ESP-IDF 中文讨论版
Topic: 通过设置全局变量I2S0,I2S1触发DMA机制的咨询
Replies: 1
Views: 2034

Re: 通过设置全局变量I2S0,I2S1触发DMA机制的咨询

I2S0全局变量不是普通的变量,是直接作用于寄存器,修改了I2S0,就等于修改了寄存器,这样就能理解了
by wulin76
Tue Jan 31, 2023 12:48 pm
Forum: ESP-IDF 中文讨论版
Topic: 关于ESP在I2C Camer从机模式下FIFO 模式的请教
Replies: 1
Views: 1878

关于ESP在I2C Camer从机模式下FIFO 模式的请教

学习ESP32摄像头的样例,例子跑通,但对于ll_cam.c(components\esp32-camera\target\esp32)中FIFO模式,确有不解,希望有人能帮忙解释 typedef enum { /* camera sends byte sequence: s1, s2, s3, s4, ... * fifo receives: 00 s1 00 s2, 00 s2 00 s3, 00 s3 00 s4, ... */ SM_0A0B_0B0C = 0, /* camera sends byte sequence: s1, s2, s3, s4, ... * fifo rece...
by wulin76
Tue Jan 31, 2023 12:36 pm
Forum: ESP-IDF 中文讨论版
Topic: 请问,哪里有demo例程下载?
Replies: 2
Views: 2178

Re: 请问,哪里有demo例程下载?

安装IDF后,在Espressif\frameworks\esp-idf-vX.X.X目录下面都有examples目录,有样例可以参考

我也是初学者,共同学习进步,:)
by wulin76
Fri Jan 27, 2023 6:44 am
Forum: General Discussion
Topic: Some doubts about the use of dma in esp32-web-camera
Replies: 2
Views: 2013

Re: Some doubts about the use of dma in esp32-web-camera

Thank you very much, I have checked the technical reference manual and the sample code to understand the usage of I2S in the sample. 1 . I2S0 in the example is working in camera slave receiver mode. 2 . If I2S wants to reset the module, you need to set the corresponding pin to 1 and then to 0. 3 . F...
by wulin76
Wed Jan 25, 2023 1:53 pm
Forum: General Discussion
Topic: Some doubts about the use of dma in esp32-web-camera
Replies: 2
Views: 2013

Some doubts about the use of dma in esp32-web-camera

Reading the code in the dma section of the esp32-web-camera project (ll_cam.c), I found that esp32, esp32s2, esp32s3 have major differences in dma, I don't understand what are the reasons for these differences? 1. esp32 defines multiple sampling modes, i2s_sampling_mode_t, what do these modes mean? ...
by wulin76
Wed Jan 25, 2023 5:18 am
Forum: ESP-IDF 中文讨论版
Topic: 通过设置全局变量I2S0,I2S1触发DMA机制的咨询
Replies: 1
Views: 2034

通过设置全局变量I2S0,I2S1触发DMA机制的咨询

在跟踪esp32-web-camera的代码时,看到了通过设置全局变量I2S0,I2S1,触发DMA的机制,对于结构体i2s_dev_t的各字段不是很理解,不懂哪里有这方面的文档,另外通过设置变量I2S0而实现DMA机制,能不能帮忙描述下? 以下是样例中,ll_cam.c中设置I2S0的代码 bool ll_cam_start(cam_obj_t *cam, int frame_pos) { I2S0.conf.rx_start = 0; I2S_ISR_ENABLE(in_suc_eof); I2S0.conf.rx_reset = 1; I2S0.conf.rx_reset = 0; I2...
by wulin76
Mon Jan 23, 2023 7:48 am
Forum: ESP-WHO 中文讨论版
Topic: OV2640,frame_size=FRAMESIZE_HD,出来的图像显示在TFTLCD屏
Replies: 3
Views: 6207

Re: OV2640,frame_size=FRAMESIZE_HD,出来的图像显示在TFTLCD屏

Crazy_L wrote: 我想问一下这个jpg2rgbz这个函数应该可以解码JPEG 格式的图片吧,为啥我在外面调用这个函数的时候会报一个很奇怪的访问指针的错误啊?
可以解压,不过性能不高,会引起watch_dog提醒
我也是想OV2640使用高清的模式,然后在TFT LCD屏显,但是不论是采用RGB565,然后自己采样,还是用摄像头JPEG输出,然后jpg2rgb565,感觉性能都不是很好,还没有找到合适的方式。