Which is the cheapest MCU that can be supported by Arduino libraries?

I have a very simple project which requires about 2 PIOs and a timer. Which is the cheapest MCU that can be supported by Arduino libraries? Is it the Atmega168?

How cheap are we talking? Is $3usd cheap, or do you want it for 50 cents? Shipping/delivery included. Which libraries are you concerned with? Is size a concern? You are going to do the soldering, can you solder surface mounted ICs ?

It is difficult to say which is cheapest, small or big.

An example, here the ATTtiny85 is cheaper than the smaller ATtiny13

Both can be programmed using the Arduino IDE, but ofcource not all librarys are supported

http://www.taydaelectronics.com/catalogsearch/result/?q=attiny

ATtiny85

…although you can get Arduino Pro Mini clones for under $4 on eBay. If you want a cheap/simple solution, that’s the one.

You want 1 or 1000? You want to load your own bootloader, or want it already loaded?

If you are just wanting one, you may want to consider an $8 arduino nano (that includes shipping).

For reasons I haven't figured out, ATtiny84A is less expensive than ATtiny85V-10 (although ATtiny85-20 may edge out the 84A). I recently ordered ten ATtiny84A-SSU for $1.06 each and ten ATtiny84A-PU for $1.15 each from Mouser. Unfortunately the DIP package is backordered :(

[quote author=Jack Christensen link=topic=183391.msg1358581#msg1358581 date=1376930339] For reasons I haven't figured out, ATtiny84A is less expensive than ATtiny85V-10 (although ATtiny85-20 may edge out the 84A). I recently ordered ten ATtiny84A-SSU for $1.06 each and ten ATtiny84A-PU for $1.15 each from Mouser. Unfortunately the DIP package is backordered :( [/quote]

All the 'V' chips are more expensive then their 'A' or 'P' equivalents.

Low voltage is a premium feature.

fungus:
All the ‘V’ chips are more expensive then their ‘A’ or ‘P’ equivalents.

Low voltage is a premium feature.

ATtiny84A

The device operates betweeb 1.8-5.5 volts.

you can get Arduino Pro Mini clones for under $4 on eBay. If you want a cheap/simple solution, that’s the one.

Yes, I agree. I’m building a swarm of little robots, so component cost is a real issue. eBay is your easy answer.

If you buy one, it costs 3.72 on Ebay, inclusive shipping. If you buy ten, it costs 3.75 each... that is weird.

You need an usb-serial-ttl converter, that is not included on the board.

ATMEGA8 dip.
10 pcs $8.44 on ebay with free shipping.

Alot of functionality for <1$

The OP vanished. He didn’t say if he wants one or a thousand. He didn’t say if he can program a standalone CPU.
Is he wanting to save $4, and spend 40 hours setting it up? OP, where are you?

jackwp: The OP vanished.

Country: Singapore City: Singapore

No activity between 1500 and 2200 Central Time. Probably in bed.

@Coding Badly, yea, sure you are right. I get inpatient sometimes. I need to work on that more.

olof_n:
ATMEGA8 dip.
10 pcs $8.44 on ebay with free shipping.

Alot of functionality for <1$

hear hear !

Thanks for all the replies. I would like to have about 10 samples. I have MKII programmer which allows me to program firmware through the SPI interface. The firmware only needs a timer to write to PIOs at certain timing.

lightaiyee: Thanks for all the replies. I would like to have about 10 samples. I have MKII programmer which allows me to program firmware through the SPI interface. The firmware only needs a timer to write to PIOs at certain timing.

As others have mentioned, ATTiny85. Internal 8Hz Oscillator makes this super easy to use.

You can have 25 for $20.25 USD, which puts it at $0.81 USD per unit. http://www.digikey.com/product-detail/en/ATTINY85-20PU/ATTINY85-20PU-ND/735469

Easily programmable and easy to use.

Here's a recent project I used it for to give you an idea how simple a circuit with it can look: http://forum.arduino.cc/index.php?topic=182906.0

The ATmega8 is hard to beat at eBay prices, if you're willing to risk eBay suppliers. (I bought some a long time ago, and they seem to work fine...) Note that the mega8 is more "directly compatible" with Arduino than the "tiny" cpus; no special installs needed or anything...