LoRa pager on M5StickC + CardKB
skuhu last edited by skuhu
i'm planning to build a small pager device, base on the M5StickC.
I would like to have a keyboard so i thinked of the CardKB.
Last but not least i want to use a LoRa Ai Thinker RA-02 Module juste as in the M5Stack LoRa Module.
The original module uses GPIO : 5/26/36 as CS/RST/IRQ.
Thats good as the M5StickC has GPIO 0/26/36 in front.
And i suppose that re-mapping GPIO 5 on GPIO 0 should be feasible.
Problem is that the RA-02 also needs MOSI/MISO/SCK that are wired to GPIO 23/19/18
and the M5Stick doesnt have more exposed GPIO.
GPIO 18/23 are used by the LCD.
As i'm new to electronics, i understand that MISO/MOSI are terms related to the SPI interface.
Is there a way to connect the needed GPIO ?
Via the Grove connector ?
As i understand the grove connector provides an I2C interface.
It seems possible to use SPI over I2C with this type of modules :
Or using these (but a bit expensive, rather have a M5Stack instead of the stick) :
grisu last edited by
It would be easier to use a Module with embedded LORA stack, which you can control with Modem AT instructions:
dda last edited by
MOSI/MISO is the SPI equivalent of Tx/Rx for UART (except the lines are not crossed: MOSI connects to MOSI, and MISO to MISO). The other difference is that's it's a bus, like I2C, with one master and one or more slaves. So you can connect a screen and a LoRa chip, for instance. However, you need a separate SS (Slave Select) line per device. You're going to have difficulties finding enough pins for this. As suggested, it'd be much better to use a managed chip (MCU + LoRa chip).
I've tried a few things but it's too cumbersome. I switched back to M5Stack for this.