Search found 8 matches

by keckert
Wed Jan 02, 2019 5:43 pm
Forum: General Discussion
Topic: RMT - problem with setting precise item duration
Replies: 4
Views: 5524

Re: RMT - problem with setting precise item duration

Calculate RMT frequencies: 80 MHz: ESP32 Source Clock frequency RMT_DIV_CNT_CHn: RMT Channel Clock Divisor RMT Channel Clock frequency = ESP32 Source Clock frequency / RMT_DIV_CNT_CHn RMT_CARRIER_HIGH_CHn: RMT Carrier Clock high duration, in ESP32 Source Clock periods RMT_CARRIER_LOW_CHn: RMT Carrie...
by keckert
Tue Aug 14, 2018 4:33 pm
Forum: General Discussion
Topic: RMT peripheral and reading a pin
Replies: 4
Views: 6296

Re: RMT peripheral and reading a pin

The RMT peripheral has an interrupt:
  • The RMT transmitter has finished transmitting the signal - rmt_set_tx_intr_en()
You could transmit your short sequence with the RMT and read your input pin with the interrupt service routine.
Sorry, I do not have example code.
by keckert
Mon Jun 04, 2018 1:43 am
Forum: Showcase
Topic: RMT IR transmit, receive test board
Replies: 0
Views: 6420

RMT IR transmit, receive test board

While working on RMT transmit and receive software, I assembled all of my test circuits on a single daughterboard for the Adafruit Huzzah32 ESP32 Feather board. It consists of three separate circuits: Transmit IR LED and 5-volt driver. This is driven by the ESP32 RMT transmit peripheral. Two IR rece...
by keckert
Sun Jun 03, 2018 11:18 pm
Forum: General Discussion
Topic: IR Transmitter
Replies: 4
Views: 20956

Re: IR Transmitter

I find very little useful information about that IR transmitter. The "datasheet" shows: 5 volt operation Two pins: signal and ground. There is a place on the board to put a surface-mount resistor, but there is no resistor mounted there. I would assume that this device is a bare IR LED. That does not...
by keckert
Sun Jun 03, 2018 10:47 pm
Forum: General Discussion
Topic: Using IR Transmitter
Replies: 0
Views: 2940

Re: Using IR Transmitter

I have successfully transmitted IR signals through the ESP32 RMT peripheral. See the GitHub
https://github.com/kimeckert/ESP32-RMT-server
for code and hardware used.
by keckert
Thu Apr 12, 2018 12:38 am
Forum: Showcase
Topic: ESP32 RMT receive app, using multiple RMT channels
Replies: 0
Views: 3923

ESP32 RMT receive app, using multiple RMT channels

ESP32 RMT application, displaying raw RMT durations from multiple receive channels. Duration data from all enabled channels are simply displayed on the monitor. This requires that the ESP32 be connected to the host computer with a USB cable. No IR protocol decode is implemented. The source compiles ...
by keckert
Wed Apr 04, 2018 3:44 pm
Forum: Showcase
Topic: ESP32 WiFi server that drives the RMT transmit peripheral
Replies: 0
Views: 3682

ESP32 WiFi server that drives the RMT transmit peripheral

This WiFi server drives low-level commands to the RMT transmitter. This allows the ESP32 to transmit any protocol that the RMT hardware and software driver supports. Compiles with ESP-IDF. The code and additional information can be found on: https://github.com/kimeckert/ESP32-RMT-server This applica...
by keckert
Tue Apr 03, 2018 9:11 pm
Forum: ESP-IDF
Topic: rmt_set_tx_carrier causes RMT error
Replies: 1
Views: 3304

rmt_set_tx_carrier causes RMT error

I am initializing the RMT transmit channel and successfully transmitting IR signals. When I try to change the carrier frequency using rmt_set_tx_carrier , the channel no longer transmits. This is true even when I write the same values that I used at initialization. I am not sure what units the high-...