nodemcu with 8input and 8output (pcf8574)

Moderators: grovkillen, Stuntteam, TD-er

Post Reply
Message
Author
megamarco83
Normal user
Posts: 151
Joined: 13 Apr 2017, 23:09

nodemcu with 8input and 8output (pcf8574)

#1 Post by megamarco83 » 15 Mar 2020, 19:31

hi, i need to have this setup:
8ch relay
8 switch input
1 nodemcu esp8266
not used serial

i used this configuration:
GPIO10 = d2 = switch1
GPIO5 = d1= switch2
GPIO4 = d2 = switch3
GPIO0 = d2 = switch4
GPIO2 = d4 = switch5
GPIO14 = d5 = switch6
GPIO12 = d6 = switch7
GPIO13 = d7 = switch8

SDA = GPIO3 = d9
SCL = GPIO1 = d10

and all relays are conected to PCF8574

it's a good configration?
all switches are momentary switches (push buttons) and they are actived only for a while (up/down of blinds) and they are activated when they goes to GND

i tryed to use GPIO16 and GPIO15 but when i put them to GND nothing happened
it's safe using GPIO10 ?
i know that GPIO0 is used for flash, but it's very remote that nodemcu reboot in in this time someone press the corresponded push button...

what's the best usage for this implementation?
thanks to all!

ps. it's falshed in DIO mode
that's better to use DOUT ?

TD-er
Core team member
Posts: 2333
Joined: 01 Sep 2017, 22:13
Location: the Netherlands
Contact:

Re: nodemcu with 8input and 8output (pcf8574)

#2 Post by TD-er » 15 Mar 2020, 20:24

Not all GPIO pins on the ESP can be used for switches as some need to have a specific state at boot. (e.g. GPIO 0, 2 and 15)
Also not all pins have a pull-up resistor (e.g. 15, 16) and not all can be used in interrupt driven code (e.g. 16)

See the documentation: https://espeasy.readthedocs.io/en/lates ... on-esp8266

User avatar
ThomasB
Normal user
Posts: 614
Joined: 17 Jun 2018, 20:41
Location: USA

Re: nodemcu with 8input and 8output (pcf8574)

#3 Post by ThomasB » 15 Mar 2020, 20:37

Also:
The relays will need to be logic level activated with input currents that do not exceed the PCF8574's recommended output currents: logic low activation that is less than 25mA or logic high that is less than 1mA.

Some 8-channel relay modules are turned on by logic low levels, some require logic high levels. Some relays support either logic that is chosen by some jumpers. And some relays modules are controlled by serial commands rather than logic levels. Be sure you have a compatible relay module for your configuration.

- Thomas

megamarco83
Normal user
Posts: 151
Joined: 13 Apr 2017, 23:09

Re: nodemcu with 8input and 8output (pcf8574)

#4 Post by megamarco83 » 15 Mar 2020, 20:43

TD-er wrote:
15 Mar 2020, 20:24
Not all GPIO pins on the ESP can be used for switches as some need to have a specific state at boot. (e.g. GPIO 0, 2 and 15)
Also not all pins have a pull-up resistor (e.g. 15, 16) and not all can be used in interrupt driven code (e.g. 16)

See the documentation: https://espeasy.readthedocs.io/en/lates ... on-esp8266
hi, yes, i know that
and i try as best solution on what i reported.
i tested it and it's working.
bu, i'm asking, if it's only luky or it can be improved.
Last edited by megamarco83 on 15 Mar 2020, 20:46, edited 2 times in total.

megamarco83
Normal user
Posts: 151
Joined: 13 Apr 2017, 23:09

Re: nodemcu with 8input and 8output (pcf8574)

#5 Post by megamarco83 » 15 Mar 2020, 20:45

ThomasB wrote:
15 Mar 2020, 20:37
Also:
The relays will need to be logic level activated with input currents that do not exceed the PCF8574's recommended output currents: logic low activation that is less than 25mA or logic high that is less than 1mA.

Some 8-channel relay modules are turned on by logic low levels, some require logic high levels. Some relays support either logic that is chosen by some jumpers. And some relays modules are controlled by serial commands rather than logic levels. Be sure you have a compatible relay module for your configuration.

- Thomas
now i'm using relays that are triggered by low activations. not so confortable, but i use reverse logic, 1=not triggered and 0=triggered
it works
i have also 1ch relay with jumper that i can choose type of activation but not yet tested

User avatar
budman1758
Normal user
Posts: 243
Joined: 15 Apr 2017, 05:13
Location: Riverside CA USA

Re: nodemcu with 8input and 8output (pcf8574)

#6 Post by budman1758 » 16 Mar 2020, 20:11

Why not use an MCP23017? 16 inputs or outputs or any mixture. Also much more output current available.
"The glass is twice as big as it needs to be".

megamarco83
Normal user
Posts: 151
Joined: 13 Apr 2017, 23:09

Re: nodemcu with 8input and 8output (pcf8574)

#7 Post by megamarco83 » 16 Mar 2020, 21:15

budman1758 wrote:
16 Mar 2020, 20:11
Why not use an MCP23017? 16 inputs or outputs or any mixture. Also much more output current available.
hi, thanks for suggestion!!
so now i have
n°8 switches (input)
and n°8 relay (output)
every blind need 2ch relay and 2 switched, so with MCP23017 what configuration you suggest to control blinds?
i mean where i should connect input and output considering GPIO of nodemcu and 16 gpio of MCP23017 ?
thanks

User avatar
budman1758
Normal user
Posts: 243
Joined: 15 Apr 2017, 05:13
Location: Riverside CA USA

Re: nodemcu with 8input and 8output (pcf8574)

#8 Post by budman1758 » 17 Mar 2020, 18:12

i mean where i should connect input and output considering GPIO of nodemcu and 16 gpio of MCP23017 ?
I imagine you can hook it up in whatever way is easiest. Use it for relays and switches and you could free up some GPIO in the nodemcu for other uses. You only need 2 GPIO for the I2C bus. You can also gang up as many MCP23017 as needed. Have fun!!
"The glass is twice as big as it needs to be".

megamarco83
Normal user
Posts: 151
Joined: 13 Apr 2017, 23:09

Re: nodemcu with 8input and 8output (pcf8574)

#9 Post by megamarco83 » 18 Mar 2020, 11:10

budman1758 wrote:
17 Mar 2020, 18:12
i mean where i should connect input and output considering GPIO of nodemcu and 16 gpio of MCP23017 ?
I imagine you can hook it up in whatever way is easiest. Use it for relays and switches and you could free up some GPIO in the nodemcu for other uses. You only need 2 GPIO for the I2C bus. You can also gang up as many MCP23017 as needed. Have fun!!
hi, i bought two mcp23017 one with pcb green and one with black pcb.
green pcb was avaliable so i have on my hands only this one now.
i see that there are differences on pins name in this two configuration board.
can you please help me on wiring boths?
with the greeen pcb i see that on right side (two raw pins)
there are: VCC -> noedmcu 3,3V
GND -> nodemcu GND
SCL -> SCL gpio on nodemcu
SDA -> SDA gpio on nodemcu

then i would like to use PA0 to PA7 for switches and PB0 to PB7 for output relay
my switches are push buttons and i need short perss and long press:
if i'm not wrong i have to set the tasks like:
task name= B_UP
switch button type=normal switch
long press event= acive on low & hight event = 10 or 11
values=B_UP

on rules i can use:

Code: Select all

//short press
on B_UP#B_UP=0 do
   Publish domoticz/in,'{"command":"setuservariable","idx":7,"value":"blind_1;Up;0.5"}'
endon
//long press
on B_UP#B_UP=10 do 
   Publish domoticz/in,'{"command":"setuservariable","idx":7,"value":"blind_1;Up;42"}'
endon

Code: Select all

on sniff#blind_1_Up=0 do MCPgpio,9,1
on sniff#blind_1_Up=1 do MCPgpio,9,0
i have to write here "9" to use MCPgpio that's connected to PB0 ??
because as far as i understand from 1 to 8 => PA0 to PA7
and from 9 to 16 => PB0 to PB7
correct?

and from wiring point of view
- push button -> one wire connected to PA0 and another wire connected to GND
- relay -> IN1 connected to PB0 and GND to GND and VCC to VCC
correct?

where i need to connect:
RST
ITA
ITB
???

now talk abot black board of mcp23017:
here i have A1 A2 A0 this three shoul connect to GND, correct?
where i have to connect RESET?

thanks

User avatar
iron
Normal user
Posts: 104
Joined: 24 Sep 2016, 08:37
Location: Veria, Greece
Contact:

Re: nodemcu with 8input and 8output (pcf8574)

#10 Post by iron » 18 Mar 2020, 15:28

Hello

RST : connect it to EPS gpio only if you have any reason to reset the MCP board. I never had the need.
ITA, ITB those are interrupt pins. You can safely ignore them.

A1 A2 A0 : are for the I2C address. No need to do anything if you only have 1 x MCP in the same I2C bus.

-D
-D

megamarco83
Normal user
Posts: 151
Joined: 13 Apr 2017, 23:09

Re: nodemcu with 8input and 8output (pcf8574)

#11 Post by megamarco83 » 19 Mar 2020, 13:01

iron wrote:
18 Mar 2020, 15:28
Hello

RST : connect it to EPS gpio only if you have any reason to reset the MCP board. I never had the need.
ITA, ITB those are interrupt pins. You can safely ignore them.

A1 A2 A0 : are for the I2C address. No need to do anything if you only have 1 x MCP in the same I2C bus.

-D
ok, understand, thanks a lot!

megamarco83
Normal user
Posts: 151
Joined: 13 Apr 2017, 23:09

Re: nodemcu with 8input and 8output (pcf8574)

#12 Post by megamarco83 » 19 Mar 2020, 13:04

but, another question related to MCP23017
if i wuold like to use it to control lights (on/off) and pushbuttons related to this, and send the status of relay to domoticz, so i can control the light using pushbuttons (gpio of mcp) or remotly using domoticz.
how i can do if i have only 12 tasks?
mcp has 16gpio
nodemcu has al least 6 usable gpio
in total 22 task should need.
because i guess that i have to create a task for relay, where i set the IDX of domoticz, so it can be aware about the relay status, and a task for every pushbutton. correct?
thanks

User avatar
iron
Normal user
Posts: 104
Joined: 24 Sep 2016, 08:37
Location: Veria, Greece
Contact:

Re: nodemcu with 8input and 8output (pcf8574)

#13 Post by iron » 19 Mar 2020, 13:54

Hello,

For output (mcpgpio,x,y) does not require to be set on any TASK you can just trigger it on demand.

For input you can set them on task but even that is not required if you monitor the pin on boot

monitor,mcp,#

-D
-D

megamarco83
Normal user
Posts: 151
Joined: 13 Apr 2017, 23:09

Re: nodemcu with 8input and 8output (pcf8574)

#14 Post by megamarco83 » 19 Mar 2020, 14:24

thanks for explanations
but....at least i need to have inside the task for every relay, otherwise how i can set the IDX of domoticz?
i mean i have to comunicate to domoticz the status, and if i trigger the relay in domoticz, espeasy should be aware of that and should trigger in proper way the relay. i'm wrong?
related to pushbutton, ok, i think that i can use rules to monitor the status of input of MCP or GPIO directly connected to nodemcu and than switch the conresponded relay.
i'm not sure to understand how the monitor cn work for this purpose

Code: Select all

monitor,mcp,#
???
i have in mind for example:

Code: Select all

On SW1#Switch=1 do
If [RL1#Switch]=1
mcpgpio,9,0
else
mcpgpio,9,1
Endif
Endon
but it means that i have to use one tast for SW1 (pushbutton)
and a task for relay (RL1)

i think that a task for relay RL1 is needed, so i can set there the IDX of domoticz
i can skip the task for pushbutton, but how i have to setup the rules using monitor function i do not understand, sorry for that.

another question, is it possible withput a task for the pushbutton, use insede the rules the longpress action?
//short press
on SW1#state=0 do
....

//long press
on SW1#state=10 do
....


thanks

User avatar
iron
Normal user
Posts: 104
Joined: 24 Sep 2016, 08:37
Location: Veria, Greece
Contact:

Re: nodemcu with 8input and 8output (pcf8574)

#15 Post by iron » 19 Mar 2020, 18:58

megamarco83 wrote:
19 Mar 2020, 14:24

another question, is it possible withput a task for the pushbutton, use insede the rules the longpress action?
//short press
on SW1#state=0 do
....

//long press
on SW1#state=10 do
....
That's were you need to start monitoring the MCP pins on boot

on System#Boot do
monitor,mcp,1
monitor,mpc,2
monitor,mcp,3
endon

Then you can handle the gpios in your conditions

-D
-D

megamarco83
Normal user
Posts: 151
Joined: 13 Apr 2017, 23:09

Re: nodemcu with 8input and 8output (pcf8574)

#16 Post by megamarco83 » 20 Mar 2020, 12:13

iron wrote:
19 Mar 2020, 18:58
megamarco83 wrote:
19 Mar 2020, 14:24

another question, is it possible withput a task for the pushbutton, use insede the rules the longpress action?
//short press
on SW1#state=0 do
....

//long press
on SW1#state=10 do
....
That's were you need to start monitoring the MCP pins on boot

on System#Boot do
monitor,mcp,1
monitor,mpc,2
monitor,mcp,3
endon

Then you can handle the gpios in your conditions

-D
sorry, not understand how it can work.
maybe i'm missing someting

Code: Select all

on System#Boot do
monitor,mcp,9
monitor,gpio,0
endon

on gpio#0 do
  if [gpio#0]=1
     mcpgpio,9,0
  else
     mcpgpio,9,1
  endif
endon
in this way i do not have any task configurated and GPIO0 is the pushbutton
mcpgpio,9 is the output (inverted relay 1=off 0=on)
but it's not working

that's the log with only one press of push button:

Code: Select all

1696476: EVENT: GPIO#0=0
1696537: ACT : mcpgpio,9,1
1696538: Command: mcpgpio
1696543: MCP : GPIO OUTPUT 9 Set to 1
1696555: EVENT: MCP#9=1
1696609: SW : GPIO=0 State=0 Output value=1
1696656: EVENT: pulsante_mcp1#State=1.00
1696876: EVENT: GPIO#0=1
1696937: ACT : mcpgpio,9,1
1696939: Command: mcpgpio
1696944: MCP : GPIO OUTPUT 9 Set to 1
1696953: EVENT: MCP#9=1
you can see that with only one press the GPIO state go at "0" and then immediatly to "1" without any pressing from my side
and the mcpgpio is always set to 1
in fact the relay is never trigger on

User avatar
iron
Normal user
Posts: 104
Joined: 24 Sep 2016, 08:37
Location: Veria, Greece
Contact:

Re: nodemcu with 8input and 8output (pcf8574)

#17 Post by iron » 21 Mar 2020, 14:29

1.
You do not realy need to monitor the mcp gpio in your application.

2.
on gpio#0 do
This condition is met twice given you have a push button so it will return. (once when gpio,0 goes high when you press it and then again when it goes low when you release it)

You can catch the action only once by :
on gpio#0=1 do
Now you only trigger the event when the input is low (or the opposite)

you may also use mcpgpiotoggle,x instead of doing it manually
on gpio#0=1 do
mcpgpiotoggle,9
endon
-D
-D

Post Reply

Who is online

Users browsing this forum: Google [Bot] and 6 guests