Arduino Forum

Using Arduino => General Electronics => Topic started by: SamRum on Aug 03, 2019, 04:40 am

Title: arduino nano nrf24l01+ st7735s
Post by: SamRum on Aug 03, 2019, 04:40 am
I am trying to connect the following devices to a Nano

nrf24l01+
st7735s
BMP280

It looks like the nrf24l01+and st7735s both use the same pins. Is it possible to redirect the pins to a different pin such as  the following
st7735s
pin 13 could be pin D6
pin 11 could be pin D5

if I am incorrect does anyone have a suggestion on how I should layout the pins connections?


From what I have read these devices use the following pins. if I am in correct with my pins usage please correct me.


nrf24l01+
ce - 3
cs - 4
mosi - 11
miso - 12
sck - 13
vcc - 3v
gnd - gnd


st7735s
a0 - 8
resist - 9
cs - 10
sda - 11
sck - 13
led+ - 3v
led- - gnd


BMP280
scl - A4
sda - A5
vcc - 3v
gnd - gnd



The end goal is to have two different devices. The sender will collect the temp every 30 seconds. After 5 minutes it will average the samples and transmit the data to the receiver and the receiver will display the temp for each receiver on the screen.

Device A receiver
Arduino nano
nrf24l01+
st7735s

Device B sender
Arduino pro mini
nrf24l01+
BMP280
Title: Re: arduino nano nrf24l01+ st7735s
Post by: raschemmel on Aug 03, 2019, 06:17 am
Did you research these devices ?
Can you tell us what protocol they use ?
Title: Re: arduino nano nrf24l01+ st7735s
Post by: Grumpy_Mike on Aug 03, 2019, 07:44 am
Quote
I am trying to connect the following devices to a Nano
Is it a 5V nano?
If so you will need signal level converters to stop the 5V signal outputs from damaging the devices.

Quote
It looks like the nrf24l01+and st7735s both use the same pins. Is it possible to redirect the pins to a different pin such as  the following
st7735s
pin 13 could be pin D6
pin 11 could be pin D5
No.

Both of those devices use an SPI interface, this is designed to allow the connection of many devices on the same set of wires. To use more than one device each one must have its own chip enable pin. This pin is put low before the software talks to the SPI bus so the chip knows it is about to be communicated with.
Title: Re: arduino nano nrf24l01+ st7735s
Post by: raschemmel on Aug 03, 2019, 10:17 am
This is called a 'bus'.

"You're either on the bus or off the bus"
Ken Kesey
Title: Re: arduino nano nrf24l01+ st7735s
Post by: Grumpy_Mike on Aug 03, 2019, 11:14 am
Might come as a surprise but I am from the UK and have no idea who Ken Kesey is or why he should say that.
Title: Re: arduino nano nrf24l01+ st7735s
Post by: raschemmel on Aug 03, 2019, 11:39 am
The Metaphor of Being on the Bus (https://wild-bohemian.com/onthebus.htm)


youre-either-on-the-bus-or-off-the-bus (https://medium.com/the-observer-is-the-observed/youre-either-on-the-bus-or-off-the-bus-6054c3d457b5)



Ken Kesey Wiki-Quote (https://en.m.wikiquote.org/wiki/Ken_Kesey)



Ken Kesey and the Merry Pranksters photo (https://www.alltreatment.com/wp-content/uploads/ci/3C39256E-4E69-4833-B7E4-2578FB791376_mw800_mh6001.jpg)


Title: Re: arduino nano nrf24l01+ st7735s
Post by: Grumpy_Mike on Aug 03, 2019, 02:42 pm
Thanks, have a Kama point.
Title: Re: arduino nano nrf24l01+ st7735s
Post by: raschemmel on Aug 03, 2019, 03:57 pm
Quote
Thanks, have a Kama point.
Thank you.

We're  all one.


Quote
The need for mystery is greater than the need for an answer.
Ken Kesey