mcu sharing pins for spi with rfm69 and an i2c device
I would like to connect an rfm69 to a small attiny (not a lot of available pins) and at least one or perhaps several i2c devices. I want to use the usart of the attiny whice means that all devices would share the same pins. Question is: does the rfm69 tri-state its spi ports when unselected?
I’ve read also about the interrupt causing rfm69 to grab the spi port but there won’t be a lot of traffic with all the devices, so I can probably work around that; moreover the rfm69 as a big enough fifo to be able to wait that the i2c transaction is done, right?
I’m unable to answer your question unfortunately but you have set me wondering what your drivers are to use an ATTiny for this job.
For now I plan to do a very crude driver as the attiny is memory constrained, but for now I have nothing concrete…
I am looking for your motivation in choosing to use the ATTiny processor rather than a device with more I/O pins.
It’s cheap and I want to make very small remote sensors, so normally the code should fit and I dont need alot of I/O. Moreover I have seen an attiny with power boost included which means very small parts count. But I did not start the project yet, that might be too tight…