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Easy - but the tmrpcm library is doing a lot of the work.. It is how I did it as well, except no library - did you look at the above link - I used pin 11 for the output - this would need to be changed to pin 9 to allow the ad card to be read using hardware spi. Try modifying my code and I'll try and...

I did post a snippet of code here https://www.flowcode.co.uk/forums/viewtopic.php?f=10&t=1147&hilit=sound&p=6284#p6284 - although this read sound from an EEPROM chip - you might be able to get it to work from SD (speed is going to be an issue) The Arduino doesn't have any sound generation hardware -...

A board like the dfplayer is probably the easeist route?

Try https://uk.banggood.com/search/dfplayer.html?from=nav

It works very well - support is good and sound quality reasonable.

Martin

Hi,

You need to use | (or) and & (and) to set or clear the relevant bits..

For example in C

Register |= 0b10; // Set bit 1
Register &= ~0b10; // Clear bit 1

Or more generally:

Register |= (1 << bit);
Register &= ~(1 << bit);

Where register is PORTA for example.


Martin

Hi Angelo, The Arduino libraries can't be used as is. Converting a library or creating a new component is a fair amount of work - but varies widely... What are you trying to use? As an aside - it is possible to use esp32 C code and add to an esp32 project. The same technique might be usab!e with oth...

Wow - that is a noisy signal! Do you have any filtering on the line? I looked at the rc-switch library and it does use the pin change interrupt to record an array of timings. This is a difficult way to debug code :-( - I wonder if there is a way you can record / send an actual signal and then a way ...

A brief attempt at a version that 'ignores' noise. Again - remove the call to SendTest to try on hardware (I'd also remove the test of issim too - it's an extra branch and sped is good here) HC12 SIm.fcfx As an aside - rather than use 'pos' and a shift to add in a 'one' bit - it might be quicker to ...

Hi Viktor, I'll think some on the noise handling over the weekend - one idea is to 'ignore' some pulses before attempting to read a message - for example 24 bits should have ~50 pin changes so ignore 250 pin changes to skip the first five messages (or so) then wait for a 'low' period. Do you know wh...

Hi Viktor, Seems to simulate OK - note that as mentioned the 'noise' handling doesn't do anything yet. Add a breakpoint at start of PinChange to simulate. This should work on hardware if you remove the SendTest(value) before the loop. The 'action' is with 'ideal' timings shown and ignoring errors. C...

A version that allows simulation. HC12 SIm.fcfx I've modified to save the data received to a single long variable instead of an array and rearranged pin change slightly - it needs to be as fast as possible - imagine a transient 'pulse' in the middle of the long low - the 'up' change will register - ...

Hi Viktor, I tried this - and no joy. Modded slightly and working again on my test rig. I think the issue is that there are several 'writes' to D2 - this will fire an interrupt and change the pin to an output (it needs to be an input) - seems to mess things up. Note the AVR chips don't have many pin...

Hi Viktor. I'm not sure what you mean by " I have to change pin B5 to pin d2" . D2 is the interrupt pin for int0 (it is fixed) and we must not write to it - if a write changes the value it will fire the interrupt which is not what we want. It should be connected to the input from the sensor. Can you...

Just had an idea for making this more 'robust' concerning noise. All the pulses are fairly long (350us+) - so if the pulse is less than a 'threshold' value (say 50us or 10us) then ignore it. This is easily done near the start of pin change with if pulse < threshold error_count = error_count + 1 else...

Hi Viktor, The Arduino library works in a slightly different way (albeit rather more complicated): 1) Record a list of pulses high/low and their lengths for complete message 2) Decode the list of pulses. This means that multiple message protocols can be handled using a single data 'recorder' with a ...

Hi Viktor, Noise will certainly cause issues if it triggers an interrupt. It would be difficult to modify the code to work on a single direction interrupt - the length of a 0 and 1 'bit' are the same - so if measuring from rise to rise the total time (4 x 350us) is the same for either value. Pin B5 ...

I got things to read and write. I modded Iain's code slightly - to run on an ATTiny85 (it was to hand) as a transmitter - sending a number (incrementing) at 1s intervals. The chip I used is running at 16.5MHz (Digistump) - and timings were slightly fast using 'delays' when viewed on the 'scope. I ad...

I think the pin change can occur at >15Hz?

The 'info' at the bottom of the dialog is for 'Timer' interrupts and I think is just a red herring?

Martin

I think the timer component should be accurate enough - I posted some code that used a high resolution timer (with a bit of C to decode the j1850 protocol (see https://www.matrixtsl.com/mmforums/viewtopic.php?f=6&t=21641&hilit=cobvert+dutch&p=98331#p98331) but it's rather more complicated) but 350us...

We looked at a couple of ways of doing this: 1) Use a 'delay' icon (So if all delays are multiples of 350us - count the number of 175us delays occurring) 2) Use a timer - and start / stop the timer. The code is all based on looking at the times at pin change however. The interrupt on pin change (Ard...

As an aside - Jan and I worked on an IR remote decoder that used a similar message structure (although the timings are much different) It might be possible to modify this code to work with this - the time handling will need some work... See https://www.flowcode.co.uk/forums/viewtopic.php?f=3&t=1120&...

Answered in the Flow code forum...

Good - progress! A couple of things you need: To access FC variables in C blocks - prefix them with FCV_ for global variables or FCL_ for local variables (and name is all uppercase - even if not so in FC) You haven't defined a lookup table - called lut1 in your C code in the interrupt handler. You h...

The password doesn't seem to be correct...

Hi Brendan,

The problem occurs because of the use of USB_Serial. The Arduino Mega doesn't support it. You'll need to switch to usindg the UART component (which lets you send/receive data via the USB port too...)
Martin

Hi dagr.

Please could you post your code-- someone will be able to help you then...

Martin