The difficulty here is that, there is no rd_gpio_num in struct esp_lcd_i80_bus_t . Only wr_gpio_num is available that means the native i80 interface in the IDF is designated to use write pin ONLY. I could define a gpio pin as rd_gpio_num and change the port gpio direction to input to manually strobe...

Hi

I am porting a new LCD graphic controller to ESP32S3 on i80 8/16-bit interface. Data write to i80 is OK and the display is working (both native 2D graphics and LVGL demo). To go further I need to read data from i80 interface as well.

Is there any guideline on this?

John

Hi There is an indirect information borrowing from Nordic's nRF52840 EVK. Its layout is open to the public(in Altium Designer format). Attached please find two screen captures : 1. File "Nordic_nRF52840_EVK_Layout1.png" shows the normal 3D view. There is a ground polygon pour around the U.FL connect...

Hi

I can find information of antenna placement for onboard antenna like attached. But that is for onboard PCB antenna. For IPEX I can't find anything similar. Maybe I have missed something?

John

Hi

I am using ESP32 S3 MINI 1U on a 4 layer PCB. The 2nd layer and the 3rd layer are ground plane.
My question is: do I need to define a cut-out area on these two ground planes underneath the IPEX connector on the MINI 1U module?

If yes, what is the dimension required?

John

b) the true reference voltage can range from 1000 mV to 1200 mV among different chips."[/url] c) The "attenuator" may have unspecified variations too Voltage reference became 873mV if we apply a measured voltage of 3100mV with 11dB (see screen shot attached.) 2023-08-21_18h06_51.png This value devi...

MicroController wrote: ↑

Sun Aug 20, 2023 1:25 pm

probably due to measurement error increasing when approaching Vref

A value as large as a 2dB gap seems too big as a measurement error. I think there is some other reasons.

Hi I am wondering how the results tabulated in the ADC Attenuation section is calculated. If I use the equation as below, the max Vin with an attenuation of 11dB should be 3.9V something, but not 3.1V. 11dB = 20*log(Vin/Vref) dB Vin = Vref * arclog(11/20) = 1100*3.548 = 3902.94mV If we really want t...

What does analogRead() return at 3v3? You don't have to reinvent the wheel. When 3.3V is applied, both analogRead() and esp_adc_cal_get_voltage() returns 3073mV. To make a comparison, two analog channels at GPIO5 (read with esp_adc_cal_get_voltage) and GPIO9(read with analogRead) are adjusted to a ...

Now it is working with the right argument for ESP32S3 (ESP_ADC_CAL_VAL_EFUSE_TP_FIT). Thanks a lot. There is a function esp_adc_cal_raw_to_voltage() to return the calibrated ADC reading but for me, the other function esp_adc_cal_get_voltage() is enough. Max. ADC voltage returns 3073mV on my board. C...