Search found 386 matches

by Deouss
Thu Apr 04, 2019 8:51 pm
Forum: Hardware
Topic: Driving an 8-bit parallel 8080 bus using I2S
Replies: 25
Views: 4710

Re: Driving an 8-bit parallel 8080 bus using I2S

Well I had no problems with I2S at 40Mhz which was max clock for ledc. However you can source-clock it with APLL clock which according to specs ranges from 16-128Mhz. I noticed that with high frequencies you must supply very stable 5V/3.3V voltage and good (2A) current for the clock source to be acc...
by Deouss
Thu Apr 04, 2019 7:00 pm
Forum: Hardware
Topic: Driving an 8-bit parallel 8080 bus using I2S
Replies: 25
Views: 4710

Re: Driving an 8-bit parallel 8080 bus using I2S

Clock limit for I2S should be in theory 80Mhz. The camera itself uses 20MHz so maybe you are doing something incorrectly.
It shouldn't be a problem even for 800x600 but it depends what refresh speeds you need
by Deouss
Thu Apr 04, 2019 6:34 pm
Forum: General Discussion
Topic: eMMC module
Replies: 19
Views: 2763

Re: eMMC module

So what read/write speeds those modules achieve?
Is it faster than WiFi?
Also that errors could be related to file size which is 4GB max for 32bit filesystem
by Deouss
Thu Apr 04, 2019 5:13 pm
Forum: Hardware
Topic: Driving an 8-bit parallel 8080 bus using I2S
Replies: 25
Views: 4710

Re: Driving an 8-bit parallel 8080 bus using I2S

It is interesting I can't see an example of TFT parallel driving with I2S however this is probably very easy. There are examples of streaming data of even 24bit in parallel. I must try it with one of my larger LCDs like ili8488. So far I used SPI but it is a bit slow for larger data. 8bit lcd should...
by Deouss
Wed Apr 03, 2019 1:34 pm
Forum: Showcase
Topic: I2S-parallel example: Drive a 64x32 display
Replies: 60
Views: 36502

Re: I2S-parallel example: Drive a 64x32 display

Those panels being rgb111 are quite overpriced. Maybe scan sections should be parallely multiplexed for better faster display.
The bitplane technique probably makes the panel flicker more frequent. WS281B panels seem to be much better
by Deouss
Mon Apr 01, 2019 5:55 pm
Forum: Showcase
Topic: I2S-parallel example: Drive a 64x32 display
Replies: 60
Views: 36502

Re: I2S-parallel example: Drive a 64x32 display

So I am investigating techniques of displaying colors on such 'scan type' panels. I didn't know that panel is only 8-color RGB - however this is case for very easy driving. This article https://www.sparkfun.com/sparkx/blog/2650 describes some tricky way of dimming led by delay times thus making it p...
by Deouss
Sat Mar 30, 2019 7:35 pm
Forum: ESP32 Arduino
Topic: Generating a HDMI signal
Replies: 4
Views: 2183

Re: Generating a HDMI signal

I just wonder - if I supply a HF signal from an external PLL with higher frequencies like 200Mhz+ - can I2S handle it?
For ESP32 cpu is jus a matter of how fast the buffers are read from dma/fifos. This could even increase the fps of cameras
by Deouss
Thu Mar 28, 2019 3:50 pm
Forum: Hardware
Topic: Can ESP32 recognize as USB mass Storage?
Replies: 5
Views: 1651

Re: Can ESP32 recognize as USB mass Storage?

martinayotte wrote: There are boards on the market that use MAX3421 as USB HOST adaptor.

Found it) They are selling full module shields
usb host spi on ali

Thanks!
by Deouss
Thu Mar 28, 2019 12:38 pm
Forum: Hardware
Topic: Can ESP32 recognize as USB mass Storage?
Replies: 5
Views: 1651

Re: Can ESP32 recognize as USB mass Storage?

ESP_Sprite wrote: As the ESP32 does not support USB natively out-of-the-box, I'd suggest finding a chip that can act as an USB host that's e.g. connected over SPI.

Could you or someone suggest such chip/IC ?
I know older usb-flash devices use serial sata-to-usb IC and might be similar to SD card interface in ESP
by Deouss
Tue Mar 26, 2019 11:41 am
Forum: Showcase
Topic: HC-SR04 using RMT - very fast
Replies: 15
Views: 4683

Re: HC-SR04 using RMT - very fast

I would like to know how many cycles a single float FPU operations take.
Why is this such a big case? I don't think it should be slower than software but I see all the time people saying it is a performance issue.
Could you please elaborate on that?

Go to advanced search