Worlds Smallest/Cheapest Computer !!! - Page 1
Forum section: electronics / general

author: paulie
author_rank: Frequent Contributor
timestamp: December 28, 2014, 08:16:07 pm
content: Introducing AVROS! I challenge anyone to come up with a smaller lower cost personal computer. The computer here being defined as able to load, store, and run programs under user control. The ability to create programs on-board may also be a consideration. Below are some photos of my Atmel Mega8 based entry.Having some idle time on my hands during this long weekend I threw together the DIP prototype. The whole thing took less than 5 minutes. Because of fine soldering a miniature QFP version took a little longer but not much. The circuit is very simple: only a chip and bypass capacitor. An LED can be added for testing and debugging but that's a luxury. In any case total cost less than a buck.On request a wiring diagram and hex file are attached. Fuses are H=c2 L=a4. In this particular image program #0 turns on the LED and returns, #5 turns off, #6 dims and loops, and #7 runs the OS again (same as reset). Of course you can load whatever others you like one byte at a time manually using ':' command or with Hyperterminal "send text file".

author: paulie
author_rank: Frequent Contributor
timestamp: December 28, 2014, 08:16:55 pm
content: The operating system, AVROS, only took me about 45 minutes to write. It talks at 57kbaud to a PC running Hyperterminal or any other serial monitor. I found it very convenient to plug in a cheap HC06 bluetooth module linked to my Android phone. Everything fits in my shirt pocket and I can play around writing little programs while killing time.Commands are as follows:'0'-'7' = run user programs (can be 8 small or one big depending on size)':' = input program in intel format (manually or via text file transfer)'a' = set address for dump'd' = dump program page in hex, 'q'=quit, any other key displays nextIf no commands are entered within 12 seconds after reset the first program in memory is executed automatically. Right now there are a few programs pre-loaded. The first one is actually the Arduino blink demo so if I don't do anything at all the LED will start flashing. There's also currently a simple calculator and a couple for checking range on nRF24l01 wireless transceivers. Another for testing an ESP8266 wifi module.If anyone is interested in building one of these let me know and I'll post a schematic and some code.

author: Seekonk
author_rank: Super Contributor
timestamp: December 28, 2014, 08:41:18 pm
content: I must be last of the big spenders. I'll stick with those on a board with a regulator, some LED and a crystal resonator for $2.25 shipped. My eyes ain't so good. But it is time we start looking at a micro as just a chip or transistor. I've just about given up analog.

author: miguelvp
author_rank: Super Contributor
timestamp: December 28, 2014, 08:47:13 pm
content: Quote from: paulie on December 28, 2014, 08:16:07 pmBOM with links where to purchase each item at those prices would be nice because I can't source an ATMEGA8-16PC for under $1 let alone adding the headers and decoupling cap.As for power I guess it's externally powered, right?

author: paulie
author_rank: Frequent Contributor
timestamp: December 28, 2014, 09:05:20 pm
content: No... Internally powered by a microscopic atomic fuel cell inside the QFP package...Of course it's externally powered like every other computer on the planet. One can hook up a rechargeable 6mm lithium button cell though and still qualify as Worlds Smallest Computer. And it will run for days.BTW I should have phrased it "WAY under a dollar". A snapshot of one of the Aliexpress listings has been added to first post. 50 cents for new parts is not the best we can do though. I've snagged refurbs for half that. At 2 for a penny the 6 pins and the 0805 cap add almost nothing. So it's quite possible to crank these out for less than half buck each.

author: paulie
author_rank: Frequent Contributor
timestamp: December 28, 2014, 09:14:57 pm
content: Quote from: Seekonk on December 28, 2014, 08:41:18 pmA quad core Pentium with 800w supply, 16 gigabyte ram, and 4 terabyte HD can be quite useful too.I also have great fondness for Pro Mini but it is far from the smallest or the cheapest (I know we all like to keep these threads on topic LOL). Fact is there are at least 2 dozen smaller MCU boards than Pro Mini and those are just the ones in my collection. A few get below an inch but nothing in the 1 cm range like this.Technically those don't qualify for "personal computer" status either since no ability to load, store, and run programs under user control as is. Best we can do there is use Arduino IDE tools to flash (1 out of 3 ain't bad). Of course one can write programs to provide these capabilities but they are not available out of the box.And at 40 cents each for m8 on Aliexpress we can build 5 of these for the cost of a single Pro Mini.

author: rob77
author_rank: Super Contributor
timestamp: December 28, 2014, 09:18:39 pm
content: Quote from: miguelvp on December 28, 2014, 08:47:13 pm+1me too.... need those 16Mhz ATmega8 MCUs under $1currently i'm getting them for 1.30Euro + VAT (would be 0.95Eur + VAT at 100+ quantitites)

author: hamdi.tn
author_rank: Frequent Contributor
timestamp: December 28, 2014, 09:21:55 pm
content: Quote from: paulie on December 28, 2014, 09:05:20 pm

author: paulie
author_rank: Frequent Contributor
timestamp: December 28, 2014, 09:25:19 pm
content: Quote from: rob77 on December 28, 2014, 09:18:39 pmIn case you missed it check post #1 again Rob... I've added a snapshot from Aliexpress for half dollar in qty 10.

author: miguelvp
author_rank: Super Contributor
timestamp: December 28, 2014, 09:33:54 pm
content: http://www.cypress.com/?mpn=CY8C4013SXI-400Qty 1: $0.40Qty 10: $0.38Qty 100: $0.35Qty 1000: $0.29Direct from manufacturer, so you know what you get.8KB Flash2KB SRAM8 pinSOIC4.8mm x 3.81mm (if you bend the pins Edit: 4 mm since the pins are 0.190mm thick) x 1.549mm.Edit: 1.27mm pitch so easy to wire it up.with 5 GPIOs, two of those are SWD Data and CLK for programming but they can be re-purposedVDD: 1.8V-5.5V with 3 decoupling caps (1 1uF, 2 0.1uF)But I'm not going to buy them just to prove a point

author: paulie
author_rank: Frequent Contributor
timestamp: December 28, 2014, 09:40:12 pm
content: Actually I did buy that exact part along with several others that were under a dollar. The ones without digital blocks are probably the cheapest ARM chips available. While not a big lover of Cypress the company I have come to appreciate the PSOC family too so thanks again for pushing me in that direction.But there is no way I could have whipped out an equivalent operating system for one of those in less than an hour. It would take weeks if not months. ARM is a great technology but IMO close to Worlds Worst Instruction Set. Maybe second only to PIC or 8051.ps. I do have my eye on STM8 which are even cheaper with beautiful architecture and instructions similar to 6502. Half the pin spacing of Mega8 can be a bitch though.

author: Dinsdale
author_rank: Regular Contributor
timestamp: December 28, 2014, 11:44:18 pm
content: That's pretty cool. But a PC? I think that's a stretch.It should have self-contained human I/O at least. I'd grant the power supply as being separate. But you should be able to draw a schematic, and lay-out a PCB on it (I mean, really, what are we doing here?). Maybe what you have there, with LCD and a membrane keyboard. Smallest size would be with the keyboard rolled up or folded for storage/carrying.

author: paulie
author_rank: Frequent Contributor
timestamp: December 29, 2014, 12:00:45 am
content: Maybe a little stretch. Let's call it poetic license.But as far as CAD, keep in mind the original IBM PC had no such capability until years later. We were lucky to get Zork up and running. Also note that many of those PCs controlled factory machines without keyboard or monitor. My cell phone makes for a very compact interface but not cheap by any means. A Hitachi type LCD would be inexpensive but requires lots of pins. I'm considering hooking up one of those cheap Nokia or OLED SPI displays and a $1 hex keypad. This would at least allow creation of programs since the current simplified OS does talk hex.Just icing on the cake though because even today many personal computers are serving embedded duty without need for fancy human interface. Sometimes just a green button and a red button.

author: Psi
author_rank: Super Contributor
timestamp: December 29, 2014, 12:11:38 am
content: You could get an old version of linux running on a STM arm micro with a little effort.That would be much more powerful and you could run/compile some of the simple linux apps for it.You would need some external ram and flash though

author: Dinsdale
author_rank: Regular Contributor
timestamp: December 29, 2014, 12:25:29 am
content: OK paulie. Laser projection virtual keyboard. Projected display. That's just a couple of piggy-backs on your chip.I know you can shrink the CAD software: 1 page schematic, 2in x 2in PCB.

author: SL4P
author_rank: Super Contributor
timestamp: December 29, 2014, 12:42:44 am
content: Seems to me that laying out a PCB to accommodate the 6-pin header, would be time just as well spent as layout for the SMD or DIP part - and get all the pins, automated assembly, physical strength etc... ?

author: paulie
author_rank: Frequent Contributor
timestamp: December 29, 2014, 01:02:34 am
content: Aside from doubling size and cost a PCB would take 5 weeks instead of 5 minutes. Not great for day after Christmas idle time project. If I were going to produce 1k units that might be the only option but so far don't look like a candidate for crowd funding. If I went with the STM8 idea maybe the only option too but a PCB would wash away the size and cost advantage of using that chip.I'm pretty happy with this construction method. In fact just for the heck of it I assembled another miniature version and it only took about 5 minutes. I'm getting better at it.

author: SL4P
author_rank: Super Contributor
timestamp: December 29, 2014, 01:07:33 am
content: Acknowledge all that - no criticism for a one-off / quickie project.It just falls short in the'worlds lowest cost computer'category, as the 10 mins to fabricate the rig for each use adds cost to the idea as a generic solution, whereas even a small panellized breakout PCB would only add - say $0.20 to the BOMNice fine soldering tho'

author: nuno
author_rank: Frequent Contributor
timestamp: December 29, 2014, 01:13:13 am
content: Since an AVR counts, let me show you my toy, besides the AVR it does input and output of sound and light, powered by a CR2032 at the back of the piezo:photo byAndré Sier.Has a ATtiny25, but I could still fit a bigger brother

author: Stonent
author_rank: Super Contributor
timestamp: December 29, 2014, 01:26:19 am
content: Not cheapest or smallest but I love this one:http://www.dos4ever.com/8031board/8031board.html8051/52 series chips, even OTP ones can be "booted" from an external eprom so you can scavenge chips from boards that you can't reprogram and use the MCS basic firmware and have a basic BASIC based computer.

author: SL4P
author_rank: Super Contributor
timestamp: December 29, 2014, 01:31:42 am
content: Quote from: Stonent on December 29, 2014, 01:26:19 amSo even if you don't like BASIC, you have a'...basic BASIC based computer.'

author: westfw
author_rank: Super Contributor
timestamp: December 29, 2014, 02:05:42 am
content: QuoteI dunno. They tend to be pretty ram-poor. unix really likes RAM.OTOH, 2.10bsd runs on some of the bigger PIC32 chips (512k flash, 128k RAM), but I haven't heard anything about it running on similarly sized ARM chips. (I guess that even the relatively small PIC32s implement a bit of virtual addressing. Interesting.)

author: dannyf
author_rank: Super Contributor
timestamp: December 29, 2014, 02:13:57 am
content: QuoteThat's my first entry into mcu, in the 1980s, where I found my first pile of gold.

author: Psi
author_rank: Super Contributor
timestamp: December 29, 2014, 02:18:31 am
content: It's not the smallest unless you use a 3x3mm DFN chip.Make something with a MC9RS08

author: westfw
author_rank: Super Contributor
timestamp: December 29, 2014, 02:19:05 am
content: Hmm. I'm not really impressed any more by the "$1 computer connects to $500 laptop via $5 USB/Serial computer" hacks.What do you think the smallest/cheapest "useful" computer would look like? SW video to your TV and input from your IR remote? One of those esp8266 modules running a Lua interpretter OVER the wifi link? (not quite there yet, I guess.) Something with BLE talking to your cellphone?I guess the core CPU/etc is no longer the limiting factor. We would need to agree on which IO devices count as "so common that their cost doesn't count", and focus on talking to them...

author: amyk
author_rank: Super Contributor
timestamp: December 29, 2014, 02:27:06 am
content: Can it run Linux...?http://dmitry.gr/index.php?proj=07.+Linux+on+8bit&r=05.Projects

author: aargee
author_rank: Frequent Contributor
timestamp: December 29, 2014, 02:58:44 am
content: I agree with John_L,Check out this 32 Bit PIC, on an 8 pin DIP form factorhttp://www.users.on.net/~tassyjim/stuff/NanoMite.pdfrunning Geoff Graham's ported version of MS Basic (http://geoffg.net/micromite.html) with an on-board editor, you just need RS232 and VT100 emulation.Quite a powerful little micro-controller/computer setup.

author: LabSpokane
author_rank: Super Contributor
timestamp: December 29, 2014, 07:03:19 am
content: Paulie,How do you go about putting together an OS for the Atmel? I've been playing around with different favors of uCs and am coming back to the Atmel just for its relative simplicity.Thanks!

author: paulie
author_rank: Frequent Contributor
timestamp: December 29, 2014, 09:53:29 am
content: If you mean from scratch I'll tell you how I'd go about it:1. Choose an MCU based on cost, memory, and peripherals required. It don't hurt to start with one of the bigger chips and scale down when done. Although historically a PIC-head, I've recently gravitated toward AVR too. Specially since adopting a bare metal philosophy and with cost and development time a factor. Those who live in HLL land might not be so particular with all the ugly details hidden from them.2. Choose toolset and test the setup with something simple like a classic blinky.. In my case I wanted to use a lowest cost chip and it was necessary to leave as much space open for user programs so assembly (AVRASM) was the obvious choice. Then maybe get serial I/O running for debugging even if the final app don't need that.3. Decide what functions are required and what's needed for I/O and the human interface then test those routines individually. In my case serial seemed to be the lowest cost interface so I started with a hello world demo. Hexdecimal input and output were next. Since loading and storing user code was required it was also necessary to test out some flash self program routines (SPM).4. Integrate all the bits and pieces and make sure they play well together. A command interpreter (get key and do something) was needed here so that tied things together. As mentioned memory space was at a premium for my app so some effort was put into reducing program size down to the minimum. Currently only only around 180 instruction words which left plenty of room for user programs. Pretty good considering what's going on.The Mega8 has a rather nice bootloader area for protecting the OS from corruption so that was nice. A Mega328 is almost as cheap and has lots more flash so it would be a great candidate if cost were not the biggest goal. In fact Mega128 with 16 times more memory yet costing only a dollar and change would be another good choice. Unless you were trying to establish a world record for smallest and cheapest like me.

author: nuno
author_rank: Frequent Contributor
timestamp: December 29, 2014, 01:15:53 pm
content: For a "computer", I would pick a relatively small and fast chip running an interpreter for some language. The interpreted code would then be stored in an external EEPROM. This way there's lots of space for code and the uC focus only on making a good interpreter, even implementing "higher" level functions to boost the interpreted language's performance. There could be a small FLASH space reserved for special user-defined routines, defined in the high level code. Ideally there would be a 3rd chip, a RAM since uCs usually have small RAM sizes, but it complicates things. This could probably be implemented under a $1 and still be very small.

author: zapta
author_rank: Super Contributor
timestamp: December 29, 2014, 05:30:56 pm
content: Quote from: aargee on December 29, 2014, 02:58:44 amThat's very neat. Small and useful out of the box. A QFN package would make it even smaller.BTW, another option for interpreted language is Forth. It's very compact and customizeable.

author: zapta
author_rank: Super Contributor
timestamp: December 29, 2014, 05:34:56 pm
content: Paulie, you can try running this interpreter. This way it will qualify as a 'real' PC ;-)http://amforth.sourceforge.net/

author: paulie
author_rank: Frequent Contributor
timestamp: December 29, 2014, 08:35:22 pm
content: I would love to run Forth on one of these chips. I had great fun with it on my old Commodore. Unfortunately there was no obvious path to implement on that site. I'll tell you a secret, if it ain't easy I'm outta here. Generally that means at the very least a hex file and wiring diagram.It's amazing how many DIY "gurus" put up hi-res photos, fancy PDFs, Eagle files, and pages and pages of source expecting noobs to install and struggle through their personal idea of a development setup. Usually involves gigabytes of bloatware and 3 week learning curve. Then they wonder why the blog dies off.Or the guys that scatter pieces all over the web. Github, youtube, Savana, blogs, Google, forums, etc with no single location for the needed info. These guys love to watch noobs dance around the world but then wonder why their project withers in the bud too.I do find interpreters fascinating and specially fond of BASIC because it's so.... that's right.... EASY! That Micromite looks interesting but I'm more into DIY than closed source "store boughten" chips. Here's a version that was open and only took a few minutes to get up and running:http://www.instructables.com/id/Single-Chip-AVR-BASIC-Computer/Flash the chip, connect to TV with clip leads, yank the keyboard from my PC and plug in, YOWZA... "OK"... ready to go. This is my kinda project.

author: LabSpokane
author_rank: Super Contributor
timestamp: December 29, 2014, 09:29:32 pm
content: Paulie,What device are you using to write to the uC? Any advice on the best choice to get one's feet wet?Thanks!

author: paulie
author_rank: Frequent Contributor
timestamp: December 29, 2014, 09:41:25 pm
content: I actually use 4 wires going to my LPT port but for most USBASP is highly recommend:http://www.ebay.com/itm/USBASP-USBISP-AVR-Programmer-Adapter-10-Pin-Cable-USB-ATMEGA8-ATMEGA128-DX-/271712366467?pt=LH_DefaultDomain_0&hash=item3f4351af83Lots more trouble free than MKII, TnyISP, or ArduinoISP. At a dollar and change each shipped it might be a good idea to pick up 2 or 3. In addition to functioning as a programmer they make an excellent target too. Cheaper than a Pro Mini.

author: LabSpokane
author_rank: Super Contributor
timestamp: December 29, 2014, 09:49:07 pm
content: Thanks! Two on order. I'm assuming that does not allow debugging. Do you handle most debugging via serial output?

author: paulie
author_rank: Frequent Contributor
timestamp: December 29, 2014, 10:02:54 pm
content: Smart move.Actually because my projects tend to be on the simple side most debugging is done with an LED. Believe it or not in addition to just on/off you can actually send out hex and/or decimal numbers. So I'd say 90% of the time LED, 9% of the time serial, and for that one out of a hundred tuffy I'll fire up AVRStudio and my Dragon.The ARM chips are much nicer for this with built-in SWIM or SWD. The STLINK debug dongles go for 2$-3$ or you can actually build one from scratch for less. Something that is not possible with Atmel. Nothing's perfect...

author: zapta
author_rank: Super Contributor
timestamp: December 30, 2014, 01:52:54 am
content: Quote from: paulie on December 29, 2014, 08:35:22 pmThat's an impressive project indeed, achieving so much with that little off the shelf hardware.

author: westfw
author_rank: Super Contributor
timestamp: December 30, 2014, 10:33:54 am
content: QuoteI'm always a bit surprised at the people who put up photos of their hand-wired hardware abominations without a PCB or even a schematic for us SW jocks to follow, without looking up a bunch of datasheets and stuff. :-)

author: paulie
author_rank: Frequent Contributor
timestamp: December 30, 2014, 01:44:57 pm
content: LOL. And I find it specially annoying when those guys offer on the 1st page to supply schematics and code for anybody who might want to build one and no only no takers but all that comes back is criticisms, complaints, and whining.

author: paulie
author_rank: Frequent Contributor
timestamp: December 30, 2014, 06:28:00 pm
content: Ok, so after receiving a couple POLITE offline requests for construction info a wiring diagram and hex file are attached to the first post. It's amazing what we can do if we use the magic word.

author: free_electron
author_rank: Super Contributor
timestamp: December 31, 2014, 09:47:30 am
content: Quote from: Psi on December 29, 2014, 12:11:38 amPff. Linux...Why don't you port the 8051 basic to an stm32. Slap on a bluetooth module to the uart and youd have a real home computer on a single chip. All you need is a terminal with bluetooth (smartphone). The code editor and runtime reside in flash, you can store programs in flash and have every single io pin avaialble. No need for a bloated operating system. Bring back the home computers that booted straight into basic in a millisecond flat.

author: mrflibble
author_rank: Super Contributor
timestamp: December 31, 2014, 06:29:17 pm
content: Quote from: free_electron on December 31, 2014, 09:47:30 amIn that regard, embedded lua looks quite interesting:http://www.eluaproject.net/overview/statushttp://www.fussylogic.co.uk/blog/?p=1222

author: paulie
author_rank: Frequent Contributor
timestamp: January 01, 2015, 01:49:29 pm
content: No direct experience with Lua but Python has been a life saver for programming on the PC. It's weird to see people struggling to do serial or menus with C#, .NET, Visual this and that, when a few minutes with script languages like these can save hours (or months). I'm amazed the full interpreter can be fit into a 256k STM chip and would love to give that a try. Unfortunately like many of these efforts there is no easy implementation on that site. No diagrams or binary available. You need to register into their secret society to get anything and even then forced to compile from scratch.I've also had some experience with small Linux distributions (Puppy. Tinycore, etc) but at best we are talking megabytes. Many years ago, back in the days of floppies, a fellow sent me a CLI version that ran off 720k. No HD involvement as I recall. But that is lost in the mists of time and it don't look like anybody will be achieving those kind of milestones again.No matter what it's doubtful any these will ever run on a 50 cent MCU.ps. I'm still thrilled by the idea of implementing a BASIC interpreter though. There are over 200 bytes left in the boot section of this Mega8 so it might be possible to squeeze in a basic BASIC interpreter. It won't quite be GW, QBASIC, or BASICA or even Palo Alto but initial experiments last night were promising.

author: mrflibble
author_rank: Super Contributor
timestamp: January 01, 2015, 04:48:31 pm
content: Quote from: paulie on January 01, 2015, 01:49:29 pmIndeed. Given the current thread audience I refrained from mentioning python to reduce the chance of afrothing event.But now that you mention it ... Embedded python also looks interesting. Basic has less appeal to me, but disregarding personal preference Basic also seems totally legit as an embedded interpreter for stm32. I'd go with either elua or embedded python, whichever happens to work out of the boxier.QuoteWhich one? You mean elua? I thought thatstep by step guidein the 2nd link was pretty doable. I certainly don't see any login requirements or some such. Maybe you mean python? That elua guide looks plausible, in that I see all the required categories ofthingsbeing addressed. But then again, maybe you prefer development under windows in which case that guide is less useful. There probably are more guides or maybe even ready to go installers. Haven't looked that hard.Quote720k? That much?!? We made do with less than that back in the day, and had to haul our own 19" racks up hill in the snow. Then walk all the way back to the village (still up hill somehow, and still snow of course) to get the slackware floppies, and and...And no I do not miss those days at all. Trying to do a big compile job on an 4 Mb machine was not exactly fast.First thing I did was get an extra 16 Mb module for HOLY SHIT THAT MUCH?!? Well worth it.But yes, sometimes I have to smile a little when I see one of those current day"space constrained"distros. But fair is fair, you tend to get more goodies installed these days, so you do get some convenience in return for the increased bloat. And with flash memory being free with a packet of cornflakes the larger install seems a reasonable tradeoff to me. Memory usage however could do with some tuning sometimes.Anyways, will be interesting to see what flavor of basic you come up with for the 50 cent mcu.

author: paulie
author_rank: Frequent Contributor
timestamp: January 02, 2015, 07:17:25 pm
content: Quote from: mrflibble on January 01, 2015, 04:48:31 pmMaybe doable but not EASY. At least from my viewpoint. Like I said if it's interesting and the creator is courteous enough to supply hex and wiring I may give something a try. That fellow expects you to not only hunt around the net for bits and pieces but then jump through his oddball os hoops to compile. Even then there's no guarantee anything will work. His comment:Quoteis a perfect example and leads me to wonder if he got his right. Anyone who was motivated enough might not hesitate to jump in but that's not me. If it were a lower cost chip like one of the $2 512k f4 dealies it might be worth it but I'm not going to spring for a $50 discovery just to gamble that he knows what he's doing.Anyway I've added a couple more keywords to the 50 cent BASIC which brings it up to 9 total:printinpoutfor...nextendinputa=a+b=a-b=Not bad for a little over hundred machine instructions. Of course they do make use of a half dozen or so BIOS calls from the original OS otherwise would take up several times more space. I've also succeeded in running a couple full blown MS type 4k-8k interpreters like the one from that link when loaded as regular apps.

author: mrflibble
author_rank: Super Contributor
timestamp: January 03, 2015, 05:09:10 pm
content: Quote from: paulie on January 02, 2015, 07:17:25 pmIs there any particular stm32 platform that is on the supported list for which you'd like a hex file? If the toolchain install happens to be straightforward I don't mind running the compile for one more target and attaching the hex file. *checks list* Okay, that basically boils down to an STM32F103 board...

author: paulie
author_rank: Frequent Contributor
timestamp: January 04, 2015, 04:12:24 pm
content: Thanks. I might like to take you up on that offer. It would be very interesting to see how well the build procedure goes for you and details on that would be appreciated.You are right that the STM103 are best candidates. Particularly STM32F103RE (ET-Stamp) which are available for a little over $2 small qty from china. I've been trying to set up a group buy with some local ARM enthusiasts but so far no bites. We could each throw together a couple STM boards significantly more powerful than what we have for $5 or so total investment. If there's a possibility to run something like Lua that would be huge motivation.Unless i"m confusing it with the ePython one there's a minimal Linux CLI shell hidden away in there too. Maybe slightly more impressive than my "AVROS".

author: Rasz
author_rank: Super Contributor
timestamp: January 06, 2015, 04:15:38 am
content: Quote from: paulie on January 04, 2015, 04:12:24 pmhow abouthttps://scargill.wordpress.com/2014/11/20/the-worlds-cheapest-computer-esp8266lua-2/

author: paulie
author_rank: Frequent Contributor
timestamp: January 07, 2015, 03:36:22 pm
content: Thanks. That looks like absolutely the worlds cheapest WIFI computer and definitely smaller than mine. Off the shelf too so no need to build anything. With Lua installed at least 100x more powerful than 50 cent BASIC.I have several of those ESP8266 modules and have been using them quite successfully for home control and security from remote locations. No attempt to program them though because there doesn't seem to be a kindergarten level tutorial around. Lots of sites but again you have to hunt around for the bits and pieces. I guess attaching everything to a blog or thread is a lost art. I may give it a try anyway if I get time some day because the rewards might turn out to be worth it.ps. Thanks to you and Mrfibble I've spent many hours now learning a new language. It wasn't quite as easy to get going as Python. Not getting to the point of being able to send serial hello world anyway.