ESP8266 SPI (Master) & MCP23S17 as PortExpander (Slave)

[rudi]

hi
just in time - i try to get on in the theme "SPI / HSPI "..
i have try this and that - but not sure - my test want not run in first time in SPI ;(
to much trouble in read in infos and threads.. and i get two OLED SPI that are not run too.

so i take my own code for bit banging the spi and make a test with a expander like the mcp23s17
it is a full 2 port expander with each 8 bit.
i show in a short youtube video the beta doing

https://www.youtube.com/watch?v=RzduRWkV2LM

and will say with this, run like a charme for me - have phun to the music too

i will managed more in this and later time i think post the project in all doing.
it is a part of a new project where esp8266 goes IoE and ..Android.. let me surprise you ..
so please understand for no beta code posting i think need time until easter
this part in going to a complette project.

best wishes rudi

i take ESP-12 and setup the pins like here:
GPIO12 MOSI
GPIO13 MISO
GPIO05 CLK
GPIO04 CS

[Adex]

You are using software SPI or hardware SPI?
I'm also using bargraph LED display to show GPIO status (+ resistor ladder).

[rudi]

You are using software SPI or hardware SPI?

In this example i use spi bit banging.
in a next video, with booting firmware from extern spi like from a micro sd with web template for webserver i use hardware spi
i upload a second bootloader likewise grub ( my own ) for choice loading firmware's, at mico sd can save more fw's .this simple upload over wifi2SPI or PC2MicroSD

I'm also using bargraph LED display to show GPIO status (+ resistor ladder).

with SPI ? where you show this?
i read only here a text.

nice but without code your example is unusable

ups.. mhm..
sure - how you see i use it useful
heads up - someday I'll even post the code.
but first try itself.
I had to learn long time to taste because it is not all documented for free in internet.
here i show - "will run if you want try"
this is a simple SPI Master - no top secrets -
try to implant spi master protocol.
posting code will not teach i think - this only be comfortable
so - try itself firsttime

best wishes
rudi

[metalphreak]

If you want to use the hardware SPI module, I've written both an SPI driver and a library that uses it for the MCP23S17:

https://github.com/MetalPhreak/ESP8266_SPI_Driver

https://github.com/MetalPhreak/ESP8266_MCP23S17

Enjoy

[rudi]

If you want to use the hardware SPI module, I've written both an SPI driver and a library that uses it for the MCP23S17:

https://github.com/MetalPhreak/ESP8266_SPI_Driver

https://github.com/MetalPhreak/ESP8266_MCP23S17

Enjoy

hihihih...
nice and clear work!
you did it professional!
did it same way after soft-spi and include oled spi.
btw: TCP_Example
netcat example was good idea! txs for this.
do you take the newest sdk?
best wishes!
rudi

[metalphreak]

I'm using the latest SDK (esp_iot_sdk_v1.0.1_15_04_24).

[luca.gamma]

If you want to use the hardware SPI module, I've written both an SPI driver and a library that uses it for the MCP23S17:

https://github.com/MetalPhreak/ESP8266_SPI_Driver

https://github.com/MetalPhreak/ESP8266_MCP23S17

Enjoy

Thanks metalphreak for sharing, do you think it is possible to drive an additional SPI slave by example using GPIO2 (I'm using an ESP-03 at present time and this is the only pin available) as a second CS_SS? My idea is to have two 16-bit ADCs to read from and then transfer samples via a TCP connection in continuous mode. Not sure if this is possible, need to check the fastest throughput with TCP without loosing frames or the network connection. An other question, is this SPI driver compatible with FreeRTOS? I may need to have an OS to separate acquisition/buffering and samples transmission tasks...

[marcelleadam]

I've double-checked the video and made some minor modifications.