65 comments

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ooooh oooooh looks sexy

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Ah bank balance, I give you fair warning……………

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Now you know it’s cruel to tease like that!

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Gertboard?
Cam. module?
Model A?
Too excited to think of anything else.

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Soon to be display?

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Yes, but not this week.

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Oooh it’s finally coming! Hey, I was wondering… does the official user guide include coverage of the Gertboard?

liz

It does. :)

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Great, thanks!

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one more reason to get the book :) thanks!!

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Very kewl except I’m getting miffed that everyone refers to ATMegaXX8s as ‘Arduinos’. An Arduino is a particular implementation using an Atmel AVR micro-controller. That’s not an Arduino above its an AVR. If this is for learning get the terminology right.

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I completely agree but ‘Arduino’ rings a bell and ‘Atmega’ not. You will find the Gertboard manuals use mostly the name Atmega.

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awesome board Gert, I would say something is only an Arduino if it uses the Arduino bootloader ……… does it ??

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You can use it with a modified loader (As the Xtal is 12 MHz) but it is much better to do without as you can program it using the SPI interface which makes it ten times faster in downloads. Also means you can re-use the boot loader space.

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Where can I pre-order it? :)

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Apparently only companies can buy from Farnell… not private persons

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To be more precise: the Gertboard is treated as normal accessory so Farnell UK only ship to UK. The branch in my country sells only to companies

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Ok, it was a bit tricky. I had to go to the “Export” site (like for countries without a local reseller) and order from there. But a bit tricky. If you could arrange to have the same ordering screen that they have for the main board would make thinks much easier for customers

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Try to put the order number (2115337) in your local Farnell//Element14/Newark order system.

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@Cyberspice, if it’s running the Arduino bootloader, it’s technically part of the Arduino family. Call it a Piduinoor something, but don’t call it ‘just an AVR’.

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But it IS just an AVR. calling a AVR a Arduino is exactly the same as calling a Raspberry Pi a fedora or a Ubuntu… And besides using without the Arduino loader gives much more freedom to use the hardware to its full potential.

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The fact that it is tagged ‘Gertboard’ is a bit of a ‘giveaway’ I reckon… but it does look like a very interesting bit of kit indeed!

As we already half way through the week, I don’t think that an ‘official announcement’ can be too far away now.

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You where right! It is there already: http://www.element14.com/raspberrypi

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Three questions…..

1) does the Arduinos development system work with it……IT WOULD be very good if it does as it would make the ideal platform!

3) Can a single power supply be used to power the board AND the PI…. IE power the PI from the expansion boards supply?

2) when / where and how much!

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1/ Yes, if you look at Gordon’s posts, he used a sample Gertboard to debug the Atmel code and he got it up and running. So you can write your code, download it and run it without
ever leaving the Pi screen.

3/ I found that the Pi USB supply suffices, provided you do not draw a lot of current from the USB plug. So I run it with only a keyboard and optical mouse and it work. (And I have a good quality 5V supply).
I will write about powering all from external later but not here or now.

2/ ….

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While the 7805 was dropped the footprint is still there so you could probablly fit something like a TSR1-2450 in there if you need wide range reasonablly efficient input.

You could also fit a 7805 and bolt a heatsink to it if you don’t care about efficiency.

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Looks good! What’s going to happen with the power regulation?

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You always find a way to make my day !!!! Hope I wont have to wait for to long to get one :)

Thanks for the good news.

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Arduino + RPi, very nice :-)

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I’m curious ’bout the pricing. Is this the start of me going electric?

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Are you currently coal fired?

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Perhaps an in-depth question.. but is the Gertboard 5v logic or 3.3v logic like the raspberry pi?

I can’t read the names on the chips, but is the most right one (replacement for q1-q5) a 3.3v-5v buffer? Is there an oscillator somewhere to provide a 8/16mhz clock or does the Gertboard use the built-in 8/16mhz resonator? (a redundant question perhaps; 8mhz is standard at 3.3v avr)

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It is 3V3, The Atmel runs at 12MHz which is already a bit above to official speed at 3V3. I have been told somebody sells an Atmel platform with a 16MHz crystal running of 3V3. But I am the old fashion type: I stick to what the manufacturer tells me.

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So it is possible for the overclocking-types to just skip soldering the 12M oscillator and add a 16, 20 or even 24M version instead.

we did some labs in in a asic course at the university and got attinys running their maximum rated speed, think was 12M, at just below 1v, way lower than the minimum req voltage of 3.3. If we fed it around 2v then there was no problem maxing the clock generator at 20M. the chips was running a benchmark software to detect glitches. Would be interesting to see the maximum freq of a ATmega running on 5v, i think atleast 32M would be possoble. probably more.

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You’re probably aware of what I’m about to say, but being able to run, and being able to perform all operations flawlessly is a completely different thing.

If you upload a program that blinks a led, you can probably put a 30mhz crystal in it and it’ll still blink that led.. But can you write to eeprom at those speeds? Can it still send data over serial? Does PWM still work? Are the timers still accurate in millisecond range (and microsecond range)?

Most of those questions must unfortunately be answered with “no” when seriously overclocking an atmega. EEprom access is one of the first things to fail, timing is all messed up preventing serial communication. The list goes on

But you can still blink that led on a digital port :D

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Actually most of them is answered “yes” :P
PWM and Timers in general work on scaled versions of system clock, so using higher clock will even give you higher resolution and accuracy.

ADC and EEPROM could have some issues, but using a suitable prescaler for the ADC should take care of that, and as for the EEPROM,if you really need it (i very seldom do) just use the CLKPR register to slow down the system clock as needed.

As for the serial interface, using a crystal with a nice multiple frequency for your serial interface of choice (UART, I2C, SPI..) the prescalers will handle the rest, and the UART of the AVRs are capable of several Mbaud. Even for low frequency the multiple of your crystal is more important then speed, for example, if you want 115200baud, the best timing you can get with 8M xtal is 7.8% error, with a 7.3728M you get 0% error. Or use 18.432M and get 0% error again. Only problem is you can not reach baudreate lower than 4800.

Arithmetic is no problem, it did not just simply blink a led, it did some check-sum calculations and then update a 7 segment display.

But yes, even if it works it is outside specs, so don’t fly airplanes with it, land on mars or use in medical care, but for home or education use it is stable enough and works just fine.

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Oh, I want it! I get to stay up all night and crash the servers again!

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You don’t have to. You can go and crash it now: http://www.element14.com/raspberrypi

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Got my pre order in. Didn’t have to crash the server to do it!

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I hope it works better than the other one, which lacks a fuse…. :)

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Damn – can someone hand me a towel, the keyboard’s covered in drool again.

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So this is going to be sold as a DIY soldering kit, presumably? Get the kiddies hooked on raspberries and then lead them on to the harder stuff? Evil plan; I like it.

I especially like that availability shouldn’t be a problem like it is with the Pi.

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Can’t promise anything about the availability. A lot of effort has gone into making enough kits available. Was the major cause for the lat arrival. However as with the Pi there is no idea if there will be 500, 5000 or 50.000 orders. If it is the last then, despite all the effort in the last few months, there will not be enough kits.

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People,

adafruit has a lot of pi loving going on:

Adafruit Raspberry Pi Educational Linux Distro,
starter kit,
sd mod,

http://www.adafruit.com/blog/category/raspberry-pi/

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Curious? Why the change from a pic to the atmel?

I have a lot of development tools for the pic.

I still can’t wait. Thank you!

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Two reasons: when I showed version 1 a lot of people moaned as they wanted the Atmel chip. But the main reason was that after trying for two days I still could not get the Pi talking reliably to the PIC over the SPI interface. I decided that, if I as very experienced engineer, could not do it in two days,then this was not the chip to give to novices. (The Atmel Pi SPI worked first time when I tried)

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Later in the week has turned out to be later in the day.
You can get all the information plus pre-ordering here: http://www.element14.com/raspberrypi
You can freely download the user manual (Which has the full schematic) , the assembly manual and a tar file containing all the example programs. The example programs are in C but we hope soon to provide Python versions (If the community does not beat us there)
There are videos showing us soldering some parts to the board especially how to solder SMD components.

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Using this board, would it it possible to control several hobby servos with Python?

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The challenge is in ‘several’ The raspberry-Pi has only on PWM output available on the GPIO connector.
You could try to make a variable pulse width in software but it is most likely to fail as Linux does not have the real time requirement to do that. Leaves using the Atmel chip on the board as “sub-contractor”. The Atmega 328 has six PWM output so you can control six servos! Your Pi has to talk to the Atmel chip (using the UART or the SPI) sending command like “Set Servos X to width Y”. the Atmel then makes your PWM signals. Good thing is that you can do all the development on the Pi for both the Pi code as well as the Atmel code! The user manual has all the information how to do that.

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Thanks for the answer!

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Seems it can be pre-ordered now for £30+VAT (£36) for us UK dwellers.

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I’ve already bought Gertboard! I can’t wait mid September…I hope delivery won’t take so much time as Rasperry Pi is being.
I have to dust down my soldering tools…

Thanks Gert for your hard work! Not only for the electronic board but also for the great and easy documentation which is free available.

Thanks Liz as well.

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ship address is Spain and no problem for the time being

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In regard to the 5V regulator, the step down from 12 to 5 at almost the max current in that little guy would make a linear regulator very hot. For those who still might want to use this as an option, Murata makes a pin compatible drop in switching replacement which will run MUCH cooler. I’ve had really good luck with them, but it is about 4 times as much as it’s linear counterpart.

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Indeed! That was the reason to drop it. But that does not prevent anybody who wants to spend the money to post solder an SMPS equivalent in place.

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Absolutely. Does that rail tie in with the Pi’s 5V leads?

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Getting a 2a supply with a good usb hub is not rare. That should be more than sufficient for Raspi + anything else you stick on there, as long as you either short out the fuse or connect directly to 5v rail

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Agreed, but in a situation where you are using a 12 volt supply to the Gertboard when running this from battery power, having a brick power supply is impractical. It would be very desirable to have a regulated supply passed along to the Pi from the Gert.

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Is it open source?

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Not the gerbers (yet).

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Can’t help noticing the 11th March copyright on the screen print – You need to find a faster pcb fab!

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I had PCBs on the 3’d of April. Prototypes working a week later. Negotiations and kitting-up took rather a bit longer.

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Excellent! *Wayne’s world guitar riff*

My pre-order is going in tonight. Can’t wait for this fantastic add on for my Pi! :)

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Newark shipped me a Raspberry Pi instead of my Gertboard. They said they are no longer selling it. Bummer.

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