Regular readers will know that I am an Ivona fan. In Node-Red I use the free Ivona service to provide high quality speech for my Raspberry Pi in Node-Red at the heart of my home control setup. Well, Ivona is now defunct. Amazon Polly is a replacement.

I’ll clarify that, Ivona is SOON to become defunct and you can’t create new accounts. The Amazon Polly system, is for most purposes a replacement for Ivona.

So – if you go to the Ivona site – you will see the reference to Amazon on the front page. The short, sharp answer is: Polly works, it is effectively free and it is as good as or better than Ivona. Read on.

So the Amazon system “Polly” works via an account. I have an Amazon Developer account and when I tried to add Polly – it said I didn’t have the right permissions – so – I added user Pete to my account and made him part of the Polly group – and that didn’t work either – then I noted something about payment and realised I’d not put any payment details in – I did that – and all of a sudden the thing came to life and I got the only things I needed – my user ID and secret password.

DON’T PANIC about payment – there is a free tier of up to (wait for it) 5 million characters per month for the first 12 months then $4 per million characters – by which point you probably won’t need any – read on) – for my purposes there is not a hope in hell I’ll ever reach the free limit. In addition  - the way I use it is the way they seem to want you to  – download a phrase as a file (MP3) and save it with a meaningful file name.  Next time you want that phrase – check to see if the file already exists – if so, play it, if not, get a new file from Amazon. In a typical use case that I might have, once the messages are used once there is very little chance of me needing to download anything and hence NO chance of incurring charges at least in the first year.

There are no doubt more elegant ways to do this than calling a command line from Node-Red and sometime someone will write a node to do it – might even be me – but right now this works perfectly and as far as I know it is the only published solution for Node-Red and Polly. If I’m wrong please do tell.

I’m assuming you have your credentials – don’t worry about location – they don’t have a location for England but all it means is to tell the code which server to use. Ireland works for me and it is working from here in Spain.

You need to grab the command line code – I used this on a Pi2.

sudo pip install awscli

Once that was in I used:

aws configure

to set up the user ID, secret key and location which I’d already set up on the Amazon site.

That done I tried this:

aws polly synthesize-speech --output-format mp3 --voice-id Amy --text "Hello my name is peter." peter.mp3

The resulting file was sitting in the /home/pi directory – this used the voice Amy (British female) to store a phrase into peter.mp3.  Good for testing but as you’ll see the final solution is much better.

The rest is about queuing messages, storing them with meaningful names, playing them back and making sure you don’t re-record a phrase you have already recorded. If you don’t like Amy – use another voice. If you want different voices for different phrases then you could incorporate the name into the filename (I’ll leave that to the reader).  If you want to add sound effects – just put .MP3 files in the relevant folder with your sound effects and call them by name.

Looking at the above diagram, a test inject passes  what you want Polly to say in the payload.

The first function looks to see if the payload has something in it and if so it pushes that onto a stack. The code then looks to see if speech is busy – if not and if there is something on the stack, it checks – if it is an mp3 file it sends the file to the MP3 player. If it is not an mp3, it looks to see if you’ve already created an mp3 for that speech, if so it plays that file, otherwise it passes the message onto Amazon to create the file – which is then played back.

It would have been nice to process new speech while playing something else back but that would get more complicated, involving more flags. As it stands this is easy to understand. You can fire in more speech or .MP3 files while one is playing and they will simply be queued.

You clearly need your Amazon account setup and Node-Red for this – you also need MPG123 player. Both Node-Red and MPG123 are in my standard script.

Here is the code I used in each of those functions…. the MPG123 exec node simply has mpg123 for the command and the append payload ticked. The AWS exec node has  aws for the command and the append payload ticked.

Here is the code for the three yellow function nodes:

if (typeof context.arr == "undefined" || !(context.arr instanceof Array)) context.arr = [];
if (typeof global.get("speech_busy") == "undefined") global.set("speech_busy", 0);

if (msg.payload !== "") context.arr.push(msg.payload);
if ((global.get("speech_busy") === 0) && (context.arr.length)) {
    msg.payload = context.arr.shift();
    global.set("speech_busy", 1);
    if (msg.payload.indexOf(".mp3") == -1) {
        var fs = global.get("fs");
        var mess = msg.payload;
        var messfile = mess.toLowerCase();
        messfile = messfile.replace(/[.,\/#!$%\^&\*;:{}=\-_`~()]/g, "");
        messfile = messfile.replace(/ /g, "_");
        
        if (fs.existsSync("/usr/audio/" + messfile + ".mp3")) {
            msg.payload = "/usr/audio/" + messfile + ".mp3";
            return [null, msg];
        }
        else {
            var voice = "Amy";
            msg.payload = 'polly synthesize-speech --output-format mp3 --voice-id ' + voice + ' --text "' + mess + '" /usr/audio/' + messfile + '.mp3';
            global.set("speech", messfile);
            return [msg, null];
        }
                    
    }
    return [null, msg]; // mp3 or synth        
}

// now play function node
msg.payload="/usr/audio/" + global.get("speech") + ".mp3";
return msg;

// clr busy function node
context.global.speech_busy=0;
msg.payload=""; return msg;

That was version 1. But ultimately I wanted new speech to be processed by Amazon WHILE a previously recorded item was playing (assuming a previously recorded item was playing and the next item had to be created).

Several hours later I came up with this – it appears to work!

and here is the latest code – probably not QUITE as straightforward to read – but when you run it – indicators on the EXEC functions (brown) show clearly that the software is able to play a recorded message while fetching a new one. Could do with some extreme testing.

if (typeof context.arr == "undefined" || !(context.arr instanceof Array)) context.arr = [];
if (typeof global.get("speech_busy") == "undefined") global.set("speech_busy", 0);
if (typeof global.get("create_speech_busy") == "undefined") global.set("create_speech_busy", 0);

if (msg.payload !== "") context.arr.push(msg.payload);
if (context.arr.length) {
    msg.payload = context.arr.shift();
    if (msg.payload.indexOf(".mp3") == -1) {
        var fs = global.get("fs");
        var mess = msg.payload;
        var messfile = mess.toLowerCase();
        messfile = messfile.replace(/[.,\/#!$%\^&\*;:{}=\-_`~()]/g, "");
        messfile = messfile.replace(/ /g, "_");
        messfile = "/usr/audio/" + messfile + ".mp3";

        if (fs.existsSync(messfile)) {
            if (global.get("speech_busy")==1) { context.arr.unshift(msg.payload);  return [null, null]; }
            else { global.set("speech_busy", 1); msg.payload = messfile; return [null, msg]; }
        }
        else {
            if (global.get("create_speech_busy")) { context.arr.unshift(msg.payload);  return [null, null]; } else
            {
            context.arr.unshift(msg.payload);
            global.set("create_speech_busy",1);
            var voice = "Amy";
            msg.payload = 'polly synthesize-speech --output-format mp3 --voice-id ' + voice + ' --text "' + mess + '" ' + messfile;
            return [msg, null];
            }
        }
    }
    if (global.get("speech_busy")==1) context.arr.unshift(msg.payload); 
    else {  global.set("speech_busy", 1); return [null, msg]; } // mp3 or synth        
}

and here, the two small function nodes

// clear creating
global.set("create_speech_busy",0);
msg.payload="";
return msg;

// clear playing
global.set("speech_busy",0);
msg.payload=""; return msg;

As a once-dedicated C programmer (I learned with the K&R book) I originally dismissed Javascript as an interpreted toy (great for websites of course), that is until I started playing with Node-Red.

At that point, after much struggle, I started to get reasonably good with it and once I got used to the string handling, C by comparison started to feel annoyingly awkward when dealing with strings and objects, despite it’s vastly superior speed.

Some time ago I looked at Espruino in a bored moment – saw that it was very much under-developed – didn’t even handle WIFI at the time – a bit pointless on an ESP8266 -  and dismissed it.

Fast forward to this week.  I had set in place some copying of files from here to Spain which, according to FTP was going to take an hour. I could not tell you why but suddenly I got the urge to go see what was happening with Espruino.

So – I believe the model here is that they developed JavaScript for a range of devices – including the ESP8266 and their funding comes from selling the boards and from contributions. I can’t help with boards right now as I have some of my own but I could not resist grabbing the code and sticking it into one of my ESP12 boards to see how they’re coming along. 

Regular readers will know that I like to revisit projects, most of the time great ideas unless they really take off, end up in the bin but just sometimes they go on to be something better.

So off I went to the site. As I’m using their software for free – here’s a push for them – take a look here  – maybe it is worth looking at one of their boards?  Anyway, I grabbed their general ESP code – and using the horrible ESPTOOL but the much prettier ESP8266FLASHER.EXE  I blew the modules into my 4MB ESP-12-E module.  I grabbed the code and followed instructions on this page.

Node the bulk of the code at 0x1000 – don’t make the mistake I made of making that 0x10000 – it won’t work and will cause hours of fun. All 4 files are in their download along with instructions.

I grabbed their web IDE (Espruino IDE) to test the code at 115K baud…. my own serial terminal does as well but theirs is prettier. For the life of my I could not get it to start up properly in their IDE – but in my terminal, on hitting reset on the ESP8266 I got this.

_____                 _

|   __|___ ___ ___ _ _|_|___ ___

|   __|_ -| . |  _| | | |   | . |

|_____|___|  _|_| |___|_|_|_|___|

          |_| http://espruino.com

1v91 Copyright 2016 G.Williams

Espruino is Open Source. Our work is supported

only by sales of official boards and donations:

http://espruino.com/Donate

Flash map 4MB:512/512, manuf 0xe0 chip 0x4016

>

Now I have to say two things – for a complete beginner I found the documentation totally confusing – making reference to LED1 which doesn’t exist and other things – but it turns out you have to read again more carefully. Secondly when I went onto their forums totally confused – two guys came in immediately and helped me.

Once I had the board responding which ultimately did not take a lot of effort – I went back to their IDE and the board was then responsive – I still don’t know why this is – but just so you know if it happens to you – you can talk to the thing with a serial terminal.

Here’s the first issue I encountered…

Every time I hit enter – the interpreter would come back with undefined. I could not fathom this out until someone pointed out that the interpreter always returns either a value – or if no value is defined, undefined…. kind of makes sense though not what you’d expect from, say, a BASIC interpreter.  Once I’d gotten to grips with this I got more ambitious.

1+2

The answer to that was “=3” – seems fair enough.

If I reset the board however I could get nothing out of their IDE – I went back to my simple serial terminal – no problem.

My next problem was following examples – one example referred to flashing a light called LED1 – turns out this doesn’t exist in their ESP8266 implementation but the ports can be expressed as numbers where 0 is GPIO0.

var  on = false;
setInterval(function() {
  on = !on;
  digitalWrite(0,on);
}, 200);

I entered the above – perfectly valid JavaScript – and blow me – it WORKED!

Of course – on resetting this would be lost unless you typed “save()” or “reset()” to clear everything out. Running that timer command with different values WITHOUT hitting reset would result in multiple timers.

So – reset – then run that code then save… and the flashing light survives power off!

Espruino does not sadly handle hardware PWM – a shame as Espressif HAVE implemented this at quite reasonable resolution (14 bits) but then their implementation is not perfect – turn it off and that timer keeps on ticking anyway – making a mess of other high speed events like SPI. So maybe that’s why they implemented software PWM – which, well, works!

Some things you should know – they’ve not implemented use of GPIO16 and space is limited at least at first glance – 12K for program storage (including OTA they only seem to use 1 Meg so that does leave nearly 3MB available on an ESP12)… you’ll find the limitations here – but to be fair many of those are ESP8266 limitations – no DAC for example – well of course there isn’t – the ESP8266 doesn’t HAVE a DAC. So the list of limitations is not as bad as it seems by any means. I’ve no idea why they did not implement GPIO16 as a simple output – I use it all the time.

What they DO have are libraries for a good number of peripherals so you might well want to take a look.

Speed? Well, they use the ESP8266 at 160Mhz by default (and that’s fine – I don’t know why we normally stick with 80Mhz given that the extra speed doesn’t take much more power) and claim that for general I/O the unit should be fast enough for general purpose use.

I used example code to connect to my WIFI – no problem – but when I tried to MQTT – I came unstuck  -their source library for MQTT simply would not load successfully.

I read that you had to put the REQUIRE into the right hand side of their IDE to load the module -  I did that and it worked but I really would like to understand how to load the module WITHOUT their IDE – as mentioned above I’m not too happy about it’s behaviour from power up.

So – armed with the MQTT library it was as simple as…

mqtt=require("MQTT").connect({
  host: "192.168.0.20",
  username: "admin",
  password: "mypass"
});

mqtt.subscribe("test/espruino");

mqtt.on('publish', function (pub) {
    console.log("topic: "+pub.topic);
    console.log("message: "+pub.message);
  });

I fired many messages at it from an MQTT publisher and sure enough  - they came in.  If one can get both WIFI and MQTT running on this interpreter and if it stays up reliably then maybe here’s yet another way to write code for the ESP8266.

To test, I disconnected the WIFI access point – and reconnected – a message came up to say MQTT was disconnected.. but on re-applying power to the WIFI access point… nothing.   When I ran the MQTT code again it connected (indicating that the WIFI connection automatically reconnected itself). What is needed now is a check for broken connection and indefinite MQTT reconnect and resubscribe attempts until it is back in running order.  If anyone has done this already – please do let us know.

http://forum.espruino.com/conversations/303129/

Lots of modules…

http://www.espruino.com/modules/

I can see this 12k storage for code being a REAL bottleneck – I do hope that gets sorted…

Here we started a conversation about SD Lifespan. How can we make our SBC projects run for longer? In comments I've seen elsewhere, people seem to think it is OK that a Pi may well fail within a year due to SD - I don't think that is even REMOTELY acceptable unless you're making a novelty games machine.  Read more as we came up with some great solutions...

Continue reading A Question of Lifespan →

What a great day. Newcastle has an annual Maker Faire and it is on this weekend – and what a faire it is.

I headed off first thing to get some parking and was pleased to find that Newcastle College had some cheap parking - £4 for the day. I arrived 45 minutes to early, thankfully the security guard was a chatty type who wanted to know what all the fuss was about so we filled in time while waiting for my friend Aidan to turn up.

We got talking about cars as that was his thing and so by the time Aidan turned up in his Tesla, the guy was itching to see it and up to his armpits in questions.

The faire started at 10am and we arrived shortly thereafter – it was CHOCKER full of people.

I’m so pleased this has turned out to be a success over the years – there was a time when “makers” – were treated a little dismissively by the public but today everyone wants to come and see what they are up to.

The first thing we came across was a self-balancing one-wheel vehicle and we had a great time talking to the designer – this is not a production job or commercial in any way, he built it because he wanted to – and it works extremely well. Yes, the pad on the front is for “emergencies”.

Rather than design in a modern way, the panelling was very retro – something my friend Melanie-Jane would love to have seen.

As we walked around we were amazed by the variety of stuff people do – from machines that do knitting, to robot hands,to retro gaming machines. A friend of ours Tony was responsible for a mini-version of the PAC-MAN arcade machine, though it had a flat top and I did remind him that the miserable pub people had this changed to round quickly as people were putting their pints on top of the machine. Well, if you’re going to spend all night playing you need somewhere to put your beer!!

Next off we came across an interesting idea – a bunch of clear tubes maybe 12” diameter and 6ft or more high – with air blowing up them. The public was provided with cups. paper plates, glue and sticky tape and invited to design the gadget likely to reach the top of the tube without falling to bits or coming back down. Aidan could not resist the challenge and so while I manned the phone he proceeded to build a very high-tech device – which actually went in – out the top and continued on for some time – no doubt setting a world record – but then – that’s what I’d expect.

If have to say, if you saw the contraption he built, there was no way this was going to fly – but it did! Flimsy as it was the device went into the tube and headed straight up at tremendous speed and cleared the top of the tube by a long way. I’ll bet the kids who were competing were hopping mad. Afraid you can’t beat a gadget man who is also an experienced, qualified pilot…

Big round of applause and we were off to get some coffee before the next challenge..

Next stop, there were LOTS of tables with things that people had made – LOTS of them – some trivial – a few flashing lights – but not this – a genuine mini-version of the old classic, the PDP-8 computer – all done with wood, loving care and a Raspberry Pi.   I’ve been planning to build an IMSAI for some time but this was just wonderful.

There can be no doubt that modern computers are fantastic – and the computers from mid-last century were toys in comparison – but the difference is – you could SEE and understand what they were doing (well, a relatively small number could – most people don’t know how their TV remote works but they’re probably not reading this blog) – it’s almost worth having one of these just as a piece of furniture – in some ways it reminds me of the bank of flashing lights on “Voyage to the bottom of the Sea” or “The Time Tunnel” and similar. But this is a real, working machine. If you can click the image and scale it up – you’ll see it was made with love.

Open source robot hands, open source 3D printers – what a combination. We met up with an old pal of ours Dave Alan – a fellow who I met at the start of the microcomputer revolution – he has speech running on a 6800 processor WAY before the big boys thought of doing it (funny enough I had the same on a PIC and have an award on the wall to prove it – then along came PC speed and that was the end of that).

We saw and had explained a new 3D Printer – no more than £350 inc. VAT which used a new recycled plastic which does not bend and warp like older materials – and I have to say, some of the parts they built with this were almost production quality – a non-technical person would not know the difference between that and a milled plastic part – VERY impressive – and not even a special heated cover over the thing!!!

Want one (but then I want a router and a laser cutter and….)

Among other delights there was a genuine dinosaur wandering around with his (her?) handler. Very impressive. Oh and you see those drawers on the right – wow – I SO miss the old radio rallies and computer shows where people brought their old junk 0 but better, suppliers brought tons of surplus stuff and sold dead cheap.  And so it was that the bearded fellow on the right – SO missed this – he decided to resurrect the idea – he had many dozens of £1 trays (3 for £2) and the prices were REAL bargains – anyway I think he’s called ABX  http://stores.ebay.co.uk/abx-labs

And that was about it – we talked to loads of people including friend Tony at the Newcastle Maker group – I hope to get to go see them in the autumn when we come back to the UK.  A GREAT day out for all the family, good prices on food – which makes a change as sometimes these things are a rip…

If you you are in the area next year, same time I strongly recommend a visit but of course such events are on all the time, all over the western world really. If nothing else you can guarantee that if you put a bunch of techies together – they’ll be dying to tell you how they made their stuff – and that is what makes these events so special. Well done to everyone involved in organising this.