Matrix user forums

Fantastic I will have a crack at that tomorrow Steve….

Relay 1 is connected active high (no pullup resistor fitted) to A4 and the other three with same configuration to C0, C1 and C2....

That is indeed the relay that I am using and the problem only occurs when a second relay is activated. If I put a 2 second delay AFTER the first relay switches on then SOMETIMES it is ok and sow times not.

I will measure voltages etc on Monday....

Yes please Steve. The PSU can supply 2.1 Amps so it isn't that and I remember that RC network business from many moons ago. The problem is that there is mains cabling crammed in everywhere in the box. On one of the black Matrix backboards it worked perfectly on the bench until I used the ECIO off th...

The relay is connected to a USB charger that I am then using to power the circuit once a momentary mains switch which bypasses the relay is pressed. So press the switch > 240V to USB charger > which produces 5V DC to power the micro > which then sends a 1 to hold the relay high. (It is just a proof ...

Never knew this because I always prototype with E-Blocks!

I'll try it now - thanks as always Ben....

Since I am using a 5V regulated supply can I skip the regulator on this board and just fit the two caps on the output side of the signal do you think Dazz?

Hi Ben,

No I don't and I knew when you read this you'd be able to help!

Do you have a rough sketch please of what I need to fit - I have those caps on that accelerometer board of yours and my hot air gun is at the ready ;-}

Hi Acestu,

It worked perfectly when it was on the ECIO Baseboard but when I try with the ECIO module on it's own then this happens. The relay module with diode is OK unfortunately!

It does have the freewheeling diode fitted - the same 1N4007 :-{

Hi Acestu,

I am controlling AC loads using 5V DC relays with all the correct transistors etc from a DC powered ECIO board!

It is this one here and it works OK until I switch AC loads where it starts "chattering" http://image0.buyincoins.com/bicv2/prod ... 020781.jpg

I have that Matrix Relay board here and will check if that helps but my relays do go through a transistor like yours...

Thanks Steve,

I am tied to 5V unfortunately hence the 5V relay but I will check your link. I think I may need a pull down but what is annoying is that by using the ECIO Base board it's OK but the ECIO on it's own keeps going haywire!!

Hi all, I am using a Matrix ECIO 28 to switch four Arduino 5V mains relays on and off and where my program starts with outputting a '1' directly to a relay to hold it high I am getting what I think is AC Ripple since the relay keeps clicking on and off as I switch the relays on and off - it "clicks"...

It very much helps Ben and I need to try a higher resistance by the sounds of it! I'm using a 1k and will try a 10k instead!

I am working on an old 5v cartridge based video game console and apparently I need to put pull down resistors on 8 data lines which is OK.

On what basis do designers decide if they should use a pull up or pull down and is there any formula to set the resistor value please....

I do not need it to be really accurate and may actually give it a shot. I want to measure changing current over 4 lines so it adds up the cost. My other solution would be to use one sensor for all four lines..

Thanks for that...

I am using John Crow's design to read current using a current sensing device and everything is fine but how about this as an idea. Since V=IR why not just put a 1% tolerance resistor from the power line rail to the ADC input directly and read the current that way? Would that work does anyone think t...

Ho does that capacitance eBlock work?


Best regards,


James :-}

I have the original white remote control from Apple which uses the same keys and agree this is a good idea...

This is the type of hand assembly and prototype work we do at prices you really wouldn't believe. This board is 0402.

In fact if anyone from the Matrix Multimedia team is reading this they should be getting quotes from us for their work. Our customers include EADS, Cooper Controls, Vishey, LG etc....

Once you have Parallels installed anything that is USB based will work perfectly and a lot of other stuff such as Parallel printer connected stuff, such as the Matrix Multimedia Dev boards that used that connection are fine with a USB to parallel port adaptor costing about a fiver from eBay. I use a...

Flowcode runs on any Apple device through Bootcamp or (better) Parallels. By using Parallels in Coherance mode you won't know the difference from it being on a Mac - all the windows etc are Mac based. As Ben Rowland or others in the Matrix Multimedia team will acknowledge I have run it on an Apple M...

Hi Brendan,

Fair point on the debugging..... If you need any prototypes building just let us know (down to 0402 on SMT) ;-}


Best regards,


James Dexter :-}

I just "compile to hex" in Flowcode and then "Import" into MPLAB and into ICD3 from there. It works perfectly....