cant change the start channel

[michaelkpierce]

Hi Jostein,
I've been using your library on a small project that I am working on. I works great when the starting channel is 1!
However, I don't seem to be able to move the Start_channel. For instance I would like the starting channel to be 20. When I change the starting channel like so
#define START_CHANNEL 20
#define NUM_CHANNELS 4
Its still working with starting channel as 1.

Is this not supposed to be the way that it works.

I suppose I can try to work around by inputing all 512 channels and then only looking for the channels that I want in the buffer.

Thanks
Michael Pierce

[SutliffeProductions]

I've not got my test rig in front of me to check this out right now, but can you post your code? Do you have this problem with the example programs?

[michaelkpierce]

Leon, Thanks for getting back to me. I am using your sample code to test right now. I have simply changed the start channel to 10 in this example but the unit still responds to start channel 1. Am i misunderstanding how it works? See code below; /* * Copyright (c) 2021 Jostein Løwer * * SPDX-License-Identifier: BSD-3-Clause * * Description: * Starts a DMX Input on GPIO pin 0 and read channel 1-3 repeatedly */ #include <Arduino.h> #include "DmxInput.h" DmxInput dmxInput; #define START_CHANNEL 10 #define NUM_CHANNELS 3 volatile uint8_t buffer[DMXINPUT_BUFFER_SIZE(START_CHANNEL, NUM_CHANNELS)]; void setup() { // Setup our DMX Input to read on GPIO 0, from channel 1 to 3 dmxInput.begin(0, START_CHANNEL, NUM_CHANNELS); // Setup the onboard LED so that we can blink when we receives packets pinMode(LED_BUILTIN, OUTPUT); } void loop() { // Wait for next DMX packet dmxInput.read(buffer); // Print the DMX channels Serial.print("Received packet: "); for (uint i = 0; i < sizeof(buffer); i++) { Serial.print(buffer[i]); Serial.print(", "); } Serial.println(""); // Blink the LED to indicate that a packet was received digitalWrite(LED_BUILTIN, HIGH); delay(10); digitalWrite(LED_BUILTIN, LOW); } Thanks again Regards Michael

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On Thu, Jun 20, 2024 at 11:40 PM Leon Sutliffe ***@***.***> wrote: I've not got my test rig in front of me to check this out right now, but can you post your code? Do you have this problem with the example programs? — Reply to this email directly, view it on GitHub <#57 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAJ77UNIF5YDWOU66XEPOFTZIPDF5AVCNFSM6AAAAABJU5HLN2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDCOBSGEYDKMJVHE> . You are receiving this because you authored the thread.Message ID: ***@***.***>

-- Regards *Michael* *916-660-2114*

[DaAwesomeP]

I'm having the same issue--no matter what it it seems to stick to channel 1.

[DaAwesomeP]

Taking a look at DmxInput.cpp, it doesn't look like start_channel or _start_channel are ever sent to the PIO or used beyond setting up the buffer.

[michaelkpierce]

The workaround is to read the whole universe into memory (plenty of memory in the PICO) and read the data you want. MP

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On Sun, Sep 8, 2024 at 12:27 PM Perry Naseck ***@***.***> wrote: I'm having the same issue--no matter what it it seems to stick to channel 1. — Reply to this email directly, view it on GitHub <#57 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAJ77UKR4WTUQF2ONVJPO4LZVSQLXAVCNFSM6AAAAABJU5HLN2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDGMZWG44TOMZRGM> . You are receiving this because you authored the thread.Message ID: ***@***.***>

-- Regards *Michael* *916-660-2114*

[DaAwesomeP]

I see. I'm using FreeRTOS and trying to keep memory small per task.

This commented out line looks like the culprit that maybe @jostlowe left unfinished:

Pico-DMX/src/DmxInput.cpp

Line 93 in c8ecde5

//pio_sm_put_blocking(pio, sm, (start_channel + num_channels) - 1);