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My Pico arrived through the letter box this morning. Good work Gordon with the delivery of the Kickstarter project.

This little project will now be alive again to roll into its second iteration after a great deal of learning from the first!

@LawrenceG I have sent you a PM.

I have some from Farnell (1850226). Imagine that is complete overkill, the ebay stuff is probably just as good.

@Gordon
There has been slow progress with the project.

However new year and its my intention to make further progress with this project. I want to design the next version which is to be compatible with the new Pico.

Would it be possible for you to create an Eagle part for the new Pico so I am able to get a head start for when it arrives?

You could use 12vDC to power everything.

Obviously you would then need a relay with a 12vDC relay coil if you are still using a relay.

If you overload a supply the voltage will start to fall. The reason the Espruino resets is that the in-rush current for the relay coil is pulling down your supply voltage.
There are usually datasheets for relays with this information on.

@lavamantis
I would suggest working back from what you are switching.

• What device on the relay are you switching? i.e. boiler, heater, light etc.
  
• The voltage and current are you switching with the relay? i.e. the device load.
  
• How long are you switching the device on for?
  
  

The ULN2003 will switch up to 500mA. The relay you are using has contacts rated at something like 10A @ given voltages. As you can see this is a big difference.

Bi-stable relays or 'flip flop' relays switch the contact state each time you energise the coil. Again it depends what you are switching. If the power fails you need to make sure it fails to a safe state!

@lavamantis - It's nice to see you progressing with your project.

Depending on your specific project requirements it might be worth investigating alternative methods of switching the DC load. Using a standard relay might not be the most efficient.

If it has to be a relay, look into using a bi-stable relay. This only requires a quick pulse to change the contact state.

Just a quick update.

ALWAYS USE PROTECTION... I should have known better really but I got lazy and there were actual flames, but no injuries!!

Connected the 24VAC GND to the DC GND and it really does not like it when using a bridge rectifier.

After a small moment of panic and further investigation, it appears the only damage was the bridge rectifier, primary side rectifier PCB tracks disintegrated and the two tiny jumper wires I was using connected directly to the 24VAC transformer were the items that caught fire.
Most importantly the Espruino is still okay, its still relatively isolated being powered via USB at the moment.

Next week I will replace the bridge rectifier with half wave rectification, use some protection on the secondary side of the transformer, make sure the wires are suitably sized and try again. In theory this should do the trick.

I have finished adding on all the input connectors and hooked up a thermistor bead on each input. They at least seem to be working just fine now.

Need to track down a 4-20mA sensor to test. I'm sure I had one kicking around!

You should be fine with the 6v.

I'm pretty pleased with it too considering its only the second PCB I have designed!

Analog outputs are generally as below.

I have been working for a while in some spare time to build my own controller for the use in building HVAC applications. I wanted to prove a few of the circuits so I squeezed as much as I could on a 10cm x 10cm board.

So this is very much just a proof of concept to check that the elements work.

SMD parts were soldered using a mini oven from Argos. I have to confess this is my first time using this method and on my first attempt I heated up the board too quickly which caused what can only be described as electronic popcorn.
The second time result is not perfect but a relative success. I set the temperature manually as required by the SMD paste temperature graph every 30 seconds.

The board has five universal inputs, selectable as follows using the jumper adjacent to each input:

• Digital input.
  
• Current 4-20mA input. Note that loop to be externally powered.
  
• Thermistor Input.
  
• Voltage 0-10vDC (Not PWM).
  
  

Four analogue outputs 0-10vDC (20mA max)

Four digital outputs via relays.

The board has a set of female headers on the back to plug the Espruino into. Note that my Espruino has the pin headers mounted in a downward direction.

I have tested some of the very basic functionality.

• Thermistor reading but not as stable as expected. Further investigation required.
  
• Only two of the analogue outputs are working correctly. Suspect this is down to the tiny resistor network components not soldered quite right.
  
• Only one relay soldered on so far but working.
  
  

Glad you got it fixed.

Don't forget you can always program the Espruino using either a 5v USB serial cable connected to the pins (with power connected to VBAT) or even the serial GPIO on the RaspberryPi connected to the Espruino serial pins.

I invested in a cheapo Saleae clone logic analyser so I can see what's going.

It was my understanding that was lacking, its starting to make a little more sense now :)

@DrAzzy - Added the console.log part as suggested.
This is what the console returns.

>digitalRead(B9)
=0
>init()
[64,0]
[0,0]
=undefined
IRQ State
>digitalRead(B9)
=1
> 

I figured I must have sent the RFM12B module some commands that must have caused it to jump into life.

I have tried sending just the first two commands and then manually sending the rest. No luck. I have had a look at different uses in other projects, all wired the same way. No reset pin.

I had another go tonight, starting from scratch rewiring all over again but I'm back square one with the IRQ line just being triggered high as soon as I send (0x0000).

I tried just sending the first two commands

setWatch(function() {
  console.log("IRQ State");
  // do next stuff
}, B9, {edge:"both", repeat:true});

function XFER(cmd) {
  SPI1.send([cmd>>8,cmd], B8);
}

SPI1.setup({sck:B3,miso:B4,mosi:B5}); // setup SPI

function init(){
  XFER(0x0000);
  XFER(0x8205);
}

WHAT THE HELL!!!! Its stopped working, I unplugged the board for some reason and then had to plug back in and reload the code and now it doesn't work.

This is what I have. I was simply running spiInit() and it was triggering the IRQ up and down.

var C = {
  // maximum transmit / receive buffer: 3 header + data + 2 crc bytes
  RF_MAX : (RF12_MAXDATA + 5),
  
  // RF12 command codes
  RF_RECV_CONTROL : 0x94A0,
  RF_RECEIVER_ON : 0x82DD,
  RF_XMITTER_ON : 0x823D,
  RF_IDLE_MODE : 0x820D,
  RF_SLEEP_MODE : 0x8205,
  RF_WAKEUP_MODE : 0x8207,
  RF_TXREG_WRITE : 0xB800,
  RF_RX_FIFO_READ : 0xB000,
  RF_WAKEUP_TIMER : 0xE000,
  
// RF12 status bits
  RF_LBD_BIT : 0x0400,
  RF_RSSI_BIT : 0x0100,

// bits in the node id configuration byte
  NODE_BAND : 0xC0, // frequency band
  NODE_ID : 0x1F, // id of this node, as A..Z or 1..31
  
  RETRIES : 8, // stop retrying after 8 times
  RETRY_MS : 1000, // resend packet every second until ack'ed

};

var RFM_IRQ = B9;
var SPI_CS = B8;
var SPI_MOSI = B5;
var SPI_MISO = B4;
var SPI_SCK = B3;

var nodeid; // address of this node
var group; // network group
var frequency; // Frequency within selected band
var rxfill; // number of data bytes in rf12_buf 
var rxstate; // current transceiver state
var ezInterval; // number of seconds between transmits
var ezSendBuf = new Array(RF12_MAXDATA); // an empty array of length 100
var ezSendLen; // number of bytes to send
var ezPending; // remaining number of retries
var ezNextSend = new Array(2); // when was last retry [0] or data [1] sent
var rf12_crc; // running crc value
var rf12_buf = new Array(RF_MAX); // recv/xmit buf, including hdr & crc bytes
var rf12_seq; // seq number of encrypted packet (or -1)
var rf12_fixed_pkt_len; // fixed packet length reception
var seqNum; // encrypted send sequence number
var cryptKey = new Array(4); // encryption key to use
//void (*crypter)(uint8_t); // does en-/decryption (null if disabled)

function XFER(cmd) {
  SPI1.send([cmd>>8,cmd], SPI_CS);
}

function spiInit() {
  SPI1.setup({sck:B3,miso:B4,mosi:B5}); // setup SPI
  XFER(0x0000); // intitial SPI transfer added to avoid power-up problem
  XFER(C.RF_SLEEP_MODE); // DC (disable clk pin), enable lbd
  // wait until RFM12B is out of power-up reset, this takes several *seconds*
  XFER(C.RF_TXREG_WRITE); // in case we're still in OOK mode
  XFER(0x80C7 | (band << 4)); // EL (ena TX), EF (ena RX FIFO), 12.0pF 
  XFER(0xA000 + frequency); // 96-3960 freq range of values within band 
  XFER(0xC606); // approx 49.2 Kbps, i.e. 10000/29/(1+6) Kbps
  XFER(0x94A2); // VDI,FAST,134kHz,0dBm,-91dBm 
  XFER(0xC2AC); // AL,!ml,DIG,DQD4 
  if (group !== 0) {
      XFER(0xCA83); // FIFO8,2-SYNC,!ff,DR 
      XFER(0xCE00 | group); // SYNC=2DXX； 
  } else {
      XFER(0xCA8B); // FIFO8,1-SYNC,!ff,DR 
      XFER(0xCE2D); // SYNC=2D； 
  }
  XFER(0xC483); // @PWR,NO RSTRIC,!st,!fi,OE,EN 
  XFER(0x9850); // !mp,90kHz,MAX OUT 
  XFER(0xCC77); // OB1，OB0, LPX,！ddy，DDIT，BW0 
  XFER(0xE000); // NOT USE 
  XFER(0xC800); // NOT USE 
  XFER(0xC049); // 1.66MHz,3.1V
}

setWatch(function() {
  console.log("IRQ State");
  // do next stuff
}, RFM_IRQ, {edge:"both", repeat:true});

That's weird. So I started again from scratch, hence the pulling all the wires out and making sure I had got the physical connections correct.

@TrapperBob, I tried swapping the MISO and MOSI but that is definitely not it. Definitely worth a try though!

I setup a setWatch on the IRQ pin to log to the console when the state changes (rising and falling).
Now when I send multiple commands I am receiving plenty of IRQ level changes on the console. I'm sure this wasn't working before and as far as I can understand this is proof that the Espruino is at least talking to the module and it is responding correctly??

Looking at the Arduino libraries for the RFM12B, I think quite a bit of the code is related to some sort of software SPI. We don't have to worry about this on the Espruino :)

Can I just check that these connections are correct.

Espruino --> RFM12B
SCK (B3) ----- SCK
MISO (B4) ----- SDI
MOSI (B5) ----- SDO
NSS_PIN (B8) ----- nSEL (active low)
IRQ (B9) ----- nIRQ (active low)

I knew it was too good to be true!

On further investigation it appears as soon as I send the first command, in this case when init() is called the first command that is sent is 0x0000, the IRQ pin goes high and stays there unless I cycle the power to the module.

Anyone got any suggestions?

Progress...

function XFER(cmd) {
SPI1.send([cmd>>8,cmd], B8);
}

var C = {
RF_SLEEP_MODE : 0x8205,
RF_WAKEUP_MODE : 0x8207,
RF_TXREG_WRITE : 0xB800
};

function init() {
// setup spi
SPI1.setup({sck:B3,miso:B4,mosi:B5});
// then...
XFER(0x0000); // intitial SPI transfer added to avoid power-up problem
XFER(C.RF_SLEEP_MODE); // DC (disable clk pin), enable lbd
// wait until RFM12B is out of power-up reset, this takes several *seconds*
XFER(C.RF_TXREG_WRITE); // in case we're still in OOK mode
while (digitalRead(B9) === 0)
XFER(0x0000);
// ...
}

Okay so good progress.
If I load the above code then digitalRead(B9) the interpreter returns 0.
Run funtion init()
Checking digitalRead(B9) returns 1

I had a look but if I'm honest I don't know where to start.

Once its connected is there any way I can just test by reading some information on it?

They operate at a lower radio frequency and you can get quite a bit more distance on them.
I have one of the wireless modules here so maybe I will have a play around. I guess I just need to connect it up to the SPI interface and work from there...

Has anyone done anything with these on the Espruino platform?
They are used extensively in other projects it would be handy to have a module for them.

Is it feasible to have the Espruino to publish and subscribe to an MQTT broker?

Just updated mine. Its only running a simple thermistor temp sensor with a PCD8544 to display the temperature but it appears to still be running okay.

Unfortunately I don't have the appropriate kit. Ideally the standard DIY reflow oven project would probably be a useful example.

I do have an example project but its work in progress right now. I need to send the PCB gerbers off to SEEED. The only problem is when I open up the files I keep tweaking stuff ;)

Yes I can't see anything being used for 136years so I think we are safe LOL.

I am calling 'compute' from setInterval.

setInterval (function() {
  p.setInput(temp);
  p.compute();
}, 1000);