2 Completely Different Questions

[TEZARM]

Hi Guys.
My first question is:
I want to make an ultrasonic reversing thing for my car. I just want the display to be a BAR of leds and a Piezo. Can someone lead me to a starting point with this project. I want to build it with a Picaxe of course.
My Second Question:
Does anyone know where I can get a multi channel voice recoreder kit from or how to make one. All the Jaycar and Dick Smith ones only have one input so you can only record one message. Dick Smith used to sell an 8 Channel Input kit but I have not seen that around for maybe 8 years. Apparently Jaycars sell a Voice recorder chip by itself, which you can design the circuit for seperately. Anyone used one of these yet? Does it only have one single input?

[Rickharris]

<A href='http://www.rev-ed.co.uk/picaxe/' Target=_Blank>External Web Link</a>
the Ultra sonic module is the easiest way to go. The US needs 30+Khz this isnt possible direct from a picaxe so the module does this on board. There have been other suggested solutions using a 555 timer to drive US TX/RX but unless cost is critical IMHO go for the module.

rev ed also do a speech synth that you can record several messages into (at a price) on the same page above.

data sheets are available and reasonably clear.

[Michael 2727]

Try datasheet SRF004.pdf for the range finder.

I can't say that I have ever heard of an 8 Ch voice recorder.
I have seen 4 message or more recorders, I
think any message was user selectable.

Oatley electronics in NSW may have had one or have a look here -
http://www.tecsol.com.au/HipTalk.htm

I only have a single 17 sec unit from a
birthday card, they could be used in a bank,
you may even get some at the &quot;reject shop&quot; or local eqivalent, they sometimes chuck
them out for a couple of bucks ea.

[Fowkc]

Rapid Electronics (here in the UK) do something that might work for you:

http://www.rapidelectronics.co.uk/rkmain.asp?PAGEID=80010&amp;CTL_CAT_CODE=&amp;STK_PROD_COD E=M35977&amp;XPAGENO=1

That's for the voice thing, obivously.

As for the ultrasonic range finder, go for the i2c version if you can afford the extra cost. It's so much easier than the pulse based one.

[hippy]

A PICAXE with PWMOUT should be able to produce the ~40kHz U/S transmit signal, and it, or a separate PICAXE, may be able to determine the delay to seeing reflection.

[TEZARM]

Thanks Rick.
Even with the US Module, would this project be quite a difficult thing to build. I would need to use 4 sensors, not 2 so I guess this makes it even more difficult yes. Is it a project that would be reliable etc to build. I guess I am wondering if it is better to buy one already made or build one. Don't care about cost but do reliabilty and complexity of code. And before someone tells me, Yes I know it would definitely be cheaper to buy one already made but if it was going to be simple enough to figure out that I would rather make it myself.

Anyone ever used either of the two modules RICK has mentioned. I am just looking for feedback on them What are they like?

[TEZARM]

Clap Clap Clap.
Good spotting Fowkc. That's exactly what I am looking for, for the speech module. Thanks. As for your comment about the Ultrasonics. I don't understand what that means. Sorry. I'm Not that smart yet.But thanks for your help.
Thanks Michael. You have some good ideas there.
Hippy, I am sure you are right with what you are saying. On the other hand, where on earth would I start. Hmmmm, you build it for me and i'll buy it off you. How does that sound. Hee Hee, just kidding. Thanks for all your help.
I am thinking that this Ultrasonic project might be a little above my knowledge unfortunately. Bugger It!

[Jo C]

TEZARM wrote: Apparently Jaycars sell a Voice recorder chip by itself, which you can design the circuit for seperately. Anyone used one of these yet? Does it only have one single input?

Jaycar sell the HK-828 voice recorder chip. There is a datasheet for it on their site, in the seimiconductor data section.

There is a Silicon Chip article on its use here:

http://www.siliconchip.com.au/cms/A_104392/article.html

I have one in my 'projects to do' drawer, when I find the time. (Yeah...right!)

[Jo C]

Just had a look at the link from Fowkc. The kit there may be based on the same chip - can't tell from the photo. The HK-828 can also record up to 8 segments.

No clues on the ultrasonics, sorry!

[frankeltham]

Re: Ultrasonics.
There are a few cheapish U/S modules available with slightly different specs and prices.

If you're in the UK try Milford Instruments
www.milinst.com and look out for Parallaxes Ping))) module at &#163;15.(In the Robotics section and they also have cheap elelctronic compass I/Fs too).
In the States you can obviously try Parallax.com.
You use a Pulsin command with PinG))) so you won't have any I2C panic attacks... its easy with supplied code samples in all Stamp formats so you can crib it easy.

I bought one a few months ago but lost it so I'm relying on memory. But I'd sooner buy another for 15 quid than fiddle for hours with transducers and amps etc. - especially as there's were nice neat tiddly SM modules.

I have seen a couple of other similar modules to Ping))) but can't remember and my dinner is ready.

[Mycroft2152]

I just saw a posting for a new ultrasonic module. The Max Sonar EZ1
<A href='http://www.wrighthobbies.net/datasheets/MaxSonar-EZ1-Datasheet.pdf
[a/]
that looks very nice and easy to use.

Myc

Note: I have no vested interest in it, just caught my eye. ' Target=_Blank>External Web Link</a>

[Mycroft2152]

Let me try that again...
I just saw a posting for a new ultra sonic module the MAX sonic EZ1

<A href='http://www.wrighthobbies.net/datasheets/MaxSonar-EZ1-Datasheet.pdf
[/a}

It looks pretty versatile and simple to use.

Myc

Note: i have no vested interest, it just caught my eye nad i've put it on my wish list. ' Target=_Blank>External Web Link</a>

[Rickharris]

If you are at all unsure stick to the Reved module for Ultra sonics. ther are easy to use - we use them in school for range finding in robots and security systems with total success. The data sheet explaines it all with code examples that are easy to understand.

if you need 4 sensors then you will have to buy 2 - this may be a little costly.

ALSO the module isnt water proof - this is most likly the biggest problem to solve. Water proof transmitter and receiver modules are available from numerious suppliers and would I expect work in place of the supplied units.

The module is built and only needs an 08 picaxe to calculate distances and 5 volts to get it going.

[Fowkc]

TEZARM: This is the &quot;basic&quot; ultrasonic module (SRF005) that you can get from Rev-Ed.

http://www.rev-ed.co.uk/docs/srf005.pdf

Basically, its output is a pulse, length proportional to the distance of the object being sensed.

When I used ultrasonic stuff for my A-level project (let it not be spoken of again), I went with the i2c version. If you've never used i2c, there's a good introduction:

http://www.rev-ed.co.uk/docs/axe110_i2c.pdf

It's basically a communications protocol for use between ICs and similar components/modules. There was an ultrasonic sensor (the SRF008) that used i2c. All you had to do was poll it once to send a pulse, and then retrieve the range data from its memory. It could also store several (up to 16 I think) echoes in memory, so you could detect more than one object. I can't find it on the PICAXE or TechSupplies sites now, but there's a page on it here:

http://www.robot-electronics.co.uk/htm/srf08tech.shtml

[TEZARM]

Frankeltham. Wow, what did ya have for dinner. I never really look forward to dinner as the cook is not the greatest cook in the world and I can basically only rely on one edible meal a week. The other nights I have to rely on the good old bottle of Tomato Sauce, as I have to smuther my meals in it to be able to swallow them without tasting them and this way I don't starve.
Anyway back to the topic. Thanks all for your replies. Hmmm, ok i take it back. Maybe the ultrasonics project isn't to difficult after all. Fowkc and Rick are making it sound easy. And with all the fantastic feedback from all of you I am thinking of sticking with the idea and going for it. Yeh, why not. I'll start tomorrow night I think. I'll keep you all posted. Thanks.
Oh yeh, thanks for that info on the voice recorder chips Jo C. Now to check out all these links and datasheets.