[Swansea Hackspace] ESP8266 wifi module

[Alan Cox]

On Tue, 09 Dec 2014 22:22:17 +0000
Justin Mitchell <justin at swansea.hackspace.org.uk> wrote:

> My order of ESP8266 modules just arrived, and they are tiny!
> 
> I bought some with the intention of being able to easily and cheaply
> (they are £2 each) add wifi to an arduino, but they are so much more.
> 
> Seems that in order to do its serial-wifi trick they embedded a cpu, an
> 80MHz 32bit cpu! And the manufacturer has just released a new version of
> the SDK, gcc tool chain, libraries and RTOS operating system for it.
> 
> The board takes 3.3v power and has UART and two GPIO (SPI, I2C, PWM
> capable) pins.
> 
> wow, talk about internet of things, you could connect a sensor and a
> small battery and make really small wireless sensors.
> 
> Latest SDK:
> https://github.com/espressif/esp_iot_rtos_sdk 
> 
> Definitely one for a future workshop i think.

Seems to have quite a lot of RAM too but looks like its one of those crap
architectures where data and code are divided 8) Fortunately it seems the
version on that board has 32K of instruction RAM and something like 80K
of data RAM. On top of that there's a ton of what looks to be mostly
reprogrammable flash memory

https://github.com/esp8266

has a ton of funky stuff for it - and it looks like it can actually do
160MHz if you aren't power constrained

http://0x04.net/~mwk/doc/xtensa.pdf

is the instruction set stuff.

Pity it doesn't have mapping tlb support, it would almost be a useful
system if it did. As it is it might be a bit tricky to get Unix on it 8-)

Alan