I have some separate 328s already! I am picking up a genuine mega board, LCD and lots of the other parts at a special price from a certain chap from china To be honest using the mega gives massive upgrade potential as the entire project is being built to be massively expandable over time. I have been picking up some good suppliers. If I can work out how to build a shield with Eagle I will give it a go.....
I get a whole genuine 1280 or 2560 board for THAT price!
how many I/O pins do you need?
ATMEGA328 has 23, 6 of which are A/D
and all for £3.60
To be honest I had been looking at how I could use the 328 so that I could just build it as one board. The graphical display was using 13 pins if I remember rightly. I think I will try and use Eagle to make a mega shield first off....
Sure, but if that pushes up your board and case size, and requires any extra connectors, etc. it might not be so clear cut.
If I can work out how to build a shield with Eagle I will give it a go.....
crikey 13 pins just for the display!!!!!
suggest you consider one that's driven using a serial interface - 2 pins maybe!
what size display are you looking at?
The problem is that the I2C displays cost more and by the time you pay the extra you might as well get the mega but it is still at the prototype stage so it's still possible to switch and I might well do that tomorrow.....
I've got something similar 99% finished - based around the open source Arduino with four sensor inputs and four trigger outputs. I'm not planning to market mine though, I just wanted something that would work for wildlife, water drops, bursting balloons, shattering glass and similar
Good luck with it
Shift Register
I can control two 20x4 HD44780 LCDs on my shield using only 4 pins from the Arduino (and I could probably take away one of those if I wanted to get real tricky). And yup, they're bog standard £6 from China parallel LCDs.
Not sure how bad the latency will be with the Arduino, but hopefully it should be short enough to catch most things (birds, bats etc).
Do you have a URL to the datasheet?I'm using the GLCD displays.
When you autoroute on Eagle, it only maps unrouted connections. So you need to "ripup" the connections you no longer want to keep to have Eagle try to autoroute them again. Very handy. I don't like the apps that auto delete hours of hard work and then screw it all up in one click.Also having moved components around to get the best fit the autorouter in Eagle is now a total scribble with tracks going through holes etc. It doesn't seem to want to totally re-route the board and I can't see an option. Any ideas?
Do you have a URL to the datasheet?
When you autoroute on Eagle, it only maps unrouted connections. So you need to "ripup" the connections you no longer want to keep to have Eagle try to autoroute them again. Very handy. I don't like the apps that auto delete hours of hard work and then screw it all up in one click.
This is with a laser from a £1 laser pointer and a simple voltage divider with a photoresistor going to one of the analogue inputs, then a digital out pin going to a 4N25 to an RF-602 transmitter, with RF-602 receiver on the flash. I set this with 0 delay to see what kind of base lag there was. Not much at all is the answer!
You'd have to adjust the pinouts to account for your display, but here's a schematic somebody did going through a 74HC595 shift register to get it down from 14 to only 5 pin outs.
Easiest way is to draw a box around the ones you want to get rid of (just a handful or all of 'em), then right click a component, select "Ripup", then right click again and select "Group: Ripup", and they'll all go back to the expected rats nest.How do you un-rip them?
Which versions of Eagle do you have? I am after version 5.7 for the Mac if anyone has it lying about
You'd have to adjust the pinouts to account for your display, but here's a schematic somebody did going through a 74HC595 shift register to get it down from 14 to only 5 pin outs.
http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1262136316
Easiest way is to draw a box around the ones you want to get rid of (just a handful or all of 'em), then right click a component, select "Ripup", then right click again and select "Group: Ripup", and they'll all go back to the expected rats nest.
The rats nest may sometimes look a little weird (still looking like routing, but with thin green lines instead of thicker blue or red ones), just click on the icon to recalculate the rats nest and it'll fix it.
Does anyone have version 5.7 for the Mac ?
Why not get the latest version? 5.11?
That's why I'm happy with my single sided and making my own boards. If I need bigger, I'll just make 2 eagle files, and chop 'em together in Photoshop.
Although, smaller boards wouldn't necessarily be a problem. Would allow you to make things more modular.
Ooooh, just seen that Sparkfun has been Slashdotted...
Now this looks VERY interesting.
http://www.sparkfun.com/products/10664
32Bit 72Mhz! 39GPIO, 16 Analogue input pins, 12-Bit ADC resolution, and 15PWM output pins with 16 Bit resolution!, 128kb flash, 20kb SRAM and a built in LiPo charger.
Think once I start hitting a wall with the Uno, that'll be my next move instead of a Mega.
I keep meaning to build something similar with an Arduino I have knocking about. Not sure how bad the latency will be with the Arduino, but hopefully it should be short enough to catch most things (birds, bats etc).
Be curious how your project is going
This is with a laser from a £1 laser pointer and a simple voltage divider with a photoresistor going to one of the analogue inputs, then a digital out pin going to a 4N25 to an RF-602 transmitter, with RF-602 receiver on the flash. I set this with 0 delay to see what kind of base lag there was. Not much at all is the answer!
Blimey!!!!!
I have JUST finished the circuit board after about 12 hours work
Much messing about of moving components was required just in order to get the circuit down to 2 layers! For those that know about these things it is going to need over a hundred vias on a 4x3.25 inch board !!
I had to remove the internal expansion connector but this is the prototype. I might have to go 4 layers for production but apparently the kit I am looking at will handle 4 layers so here's hoping. Saying that though and IF as most people who said they want it do so then I might be able to get the PCBs made externally.
Well I've learnt that you need to pick up components and wobble them to make sure the tracks are connected!! I have managed to get about 80% of the board onto the schematic and then bring up the PCB. Using 2 layers Eagle cannot route all the tracks and fails with 2 so it would have to be a 4 layer board or as I would probably do 2 wire connects Might go for 4 layers for production.
Well Eagle isn't doing it's best to suggest I spend so much money. It was all working well and now components that I add to the schematic don't automatically appear on the PCB. If I try and add them to the PCB I get errors about inconsistent connects etc....
That's exactly the answer I was hoping for, awesome work
Looking at multiplexers and PISO shift registers like the 165, 4051 and 4067.
How quick it'll be to respond then I don't know, but will be testing. Whether I used a multiplexer or went straight into the Arduino's pins, I don't think it wouldn matter, I'd still have to check each of the pins one at a time. It'd slow detection speed down by 1/6th or 1/8th (depending on how many sensors I hooked up). But, that may still be fast enough. Only one way to find out.
As (presumably) you don't care which one triggered why not use open collector triggers on a single interrupt line.
I'm glad you guys know all the technical jargon you're talking about
er - oh yes it does!
they're normally loitering just south of the board - you need to zoom out to see them
if you use the mouse scroll wheel to zoom, hold it over the opposite corner
it zooms centred on the mouse position
just thought - wonder if you've hit a "maximimum component count on free version" limit?