Move over, Raspberry Pi, your number's up !

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jack
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#16

Post by jack »

simon wrote:...C's C though right?
Yes, it is.

Driving an LCD is quite straightforward - the main type of character LCD controller is the HD44780U - its easy to drive and there are standard chunks of code you can cut & paste for it - the original spec allowed for up to 2 rows of 40 characters with a few "user defined" characters that you could load yourself - many "HD44780-compatible" controllers allow 4 rows x 16 characters etc.

Do not attempt to write your own LCD or I2C libraries if you are starter - just ask and one will magically appear.... (there are quite a lot out there, many of which are rubbish, but there you go...)

If you go the Arduino route, many libraries are available for free - the language is called "Wiring" (although its simply C or C++), the program as a whole is termed a "Sketch", and the underlying compiler is avr-gcc, the same as used by Atmel in AVRStudio...
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simon
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#17

Post by simon »

Still finding all the different boards a bit confusing to be honest. Let's say I want to start with an LCD screen and get to grips with that. I could go for AVR-MT for 30 euros, or AVR-MT128 for 34 euros, the latter having buttons to play with too. Then do I just need a programmer? Say one of these AVR-ISP-MK2 for 20 euros.

If I wanted to get separate bits presumably I'd need an LCD for a few quid, say one of these:
http://www.ebay.co.uk/itm/1pcs-1602-16x ... 27daca71cd

http://www.ebay.co.uk/itm/HD44780-Backl ... 41797ba426

http://www.ebay.co.uk/itm/HD44780-Backl ... 417d0d8e6e

Then a chip, like this?
http://www.ebay.co.uk/itm/New-1-pcs-8-B ... 19d3ca80a7

Something to plug the chip in to - one of the Olimex boards perhaps, but I don't know which. Plus some cables to connect it all together?

And a programmer like before, perhaps one of these. It's a quarter of the price so I can't help wonder what it doesn't do that the more expensive one does?

Am I on the right lines???
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ed
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#18

Post by ed »

simon wrote: Am I on the right lines???
I use one of these. Not the cheapest but it's totally compatible with studio6 and it's just a matter of re-plugging the jumper wires to program different chips. I had to solder the 40pin zif(zero insertion force) socket on the right hand side, but its easily the best method of plugging in the patient. There are no lcds or buttons on this one though.


http://www.atmel.com/tools/AVRDRAGON.aspx

you can get usb programmers for as little as £5 if you want to save money, as you've already found out....just put in attiny or atmega programmer to your browser....choices, choices.

be aware that some of the new avr xmega chips are surface mount only.....puts them out of reach of the casual fiddler.

your £4.50 programmer is comprehensive...you just have to build the board with the socket for the patient and the jumper pins to connect the 6 pins on the £4.50 unit to the 6 pins that are used on the patient chip....its more resilient to use jumpers because the different chips are programmed through different pins....hope that makes some sense. The 6 pin programming method is called ISP. Some older technologies may refer to this with 10 pin connection, so don't be alarmed.

most of the stuff I've done recently I've managed to do with attiny461, which are 20 pin and £1 each from RS. This pre-amp project which I resurrected was originally with tiny461 and worked ok but I needed more pins so I moved to atmega48, which are still only £1.50 from RS. They're not going to break the bank....and they are re-usable if you're penny pinching.
It's a quarter of the price so I can't help wonder what it doesn't do that the more expensive one does?
The more expensive programmers like the dragon allow communication with studio so that you can simulate stuff in a test environment....it's harder to do this with the basic units.
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