MAX6675 thermocouple not working

Menno Bakker

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Jul 23, 2022, 12:23:09 PM7/23/22

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I used Tasmotizer 1.2.1 to install tasmota-sensors version 12.0.2 on a Wemos D1 Mini.

A MAX6675 thermocouple is connected through SPI.

D6 = MISO

D5 = SCLK

D8 = CS

GND connected and 5 V to Vcc.

MQTT has been set up and is running, I can see the time being published, but no temperatures:

config = {"ip":"192.168.178.76","dn":"Tasmota","fn":["Tasmota",null,null,null,null,null,null,null],"hn":"tasmota-A82505-1285","mac":"840D8EA82505","md":"Generic","ty":0,"if":0,"ofln":"Offline","onln":"Online","state":["OFF","ON","TOGGLE","HOLD"],"sw":"12.0.2","t":"tasmota_A82505","ft":"%prefix%/%topic%/","tp":["cmnd","stat","tele"],"rl":[0,0,0,0,0,0,0,0],"swc":[-1,-1,-1,-1,-1,-1,-1,-1],"swn":[null,null,nul…

sensors = {"sn":{"Time":"2022-07-23T15:02:21"},"ver":1}

The MAX6675 has been verified to work on an Arduino Uno.

What am I missing or doing wrong?

Kind regards,

Menno

billy jack newman

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Jul 23, 2022, 12:25:50 PM7/23/22

to Menno Bakker, TasmotaUsers

It shows null for sensor in that message, when you log into unit with ip, does it show the temp?

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Menno Bakker

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Jul 23, 2022, 12:31:47 PM7/23/22

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No, I can't see the temp on the web interface, or in the console.

I tried the command to switch to MAX6675 on the console to no avail.

It seems the sensor is not being picked up at boot.

00:00:00.001 HDW: ESP8266EX
00:00:00.050 CFG: Loaded from flash at FA, Count 26
00:00:00.056 QPC: Count 1
00:00:00.062 SPI: Software using GPIO14(CLK) and GPIO12(MISO)
00:00:00.069 Project tasmota - Tasmota Version 12.0.2(sensors)-2_7_4_9(2022-06-20T12:44:35)
00:00:00.511 WIF: Connecting to AP1 ***************** Channel 6 BSSId 1C:ED:6F:0F:B5:24 in mode 11n as tasmota-A82505-1285...
00:00:04.754 WIF: Connected
00:00:05.008 HTP: Web server active on tasmota-A82505-1285 with IP address 192.168.178.76
00:00:06.540 QPC: Reset
17:30:04.031 MQT: Attempting connection...
17:30:04.068 MQT: Connected
17:30:04.071 MQT: tele/tasmota_A82505/LWT = Online (retained)
17:30:04.073 MQT: cmnd/tasmota_A82505/POWER =
17:30:04.080 MQT: tele/tasmota_A82505/INFO1 = {"Info1":{"Module":"Generic","Version":"12.0.2(sensors)","FallbackTopic":"cmnd/DVES_A82505_fb/","GroupTopic":"cmnd/tasmotas/"}}
17:30:04.090 MQT: tele/tasmota_A82505/INFO2 = {"Info2":{"WebServerMode":"Admin","Hostname":"tasmota-A82505-1285","IPAddress":"192.168.178.76"}}
17:30:04.102 MQT: tele/tasmota_A82505/INFO3 = {"Info3":{"RestartReason":"External System","BootCount":11}}
17:30:08.440 MQT: tele/tasmota_A82505/STATE = {"Time":"2022-07-23T17:30:08","Uptime":"0T00:00:13","UptimeSec":13,"Heap":23,"SleepMode":"Dynamic","Sleep":50,"LoadAvg":19,"MqttCount":1,"Wifi":{"AP":1,"SSId":"*****************","BSSId":"1C:ED:6F:0F:B5:24","Channel":6,"Mode":"11n","RSSI":44,"Signal":-78,"LinkCount":1,"Downtime":"0T00:00:06"}}

Op zaterdag 23 juli 2022 om 18:25:50 UTC+2 schreef billyj...@gmail.com:

Philip Knowles

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Jul 23, 2022, 2:09:03 PM7/23/22

to Menno Bakker, TasmotaUsers

Try downloading tasmota-sensors.bin from Tasmota ESP8266 Binaries and do an OTA update (download minimal too and do that first) just in case something got corrupted.

If it still doesn’t work go into console and restart 1 and look at the error messages you get

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Menno Bakker

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Jul 23, 2022, 2:43:43 PM7/23/22

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Did that. No error messages. Tried another D1 Mini, does not work either.

00:00:00.001 HDW: ESP8266EX

00:00:00.046 CFG: Loaded from flash at F9, Count 11
00:00:00.051 QPC: Count 1
00:00:00.058 SPI: Software using GPIO14(CLK) and GPIO12(MISO)
00:00:00.064 Project tasmota - Tasmota Version 12.0.2(sensors)-2_7_4_9(2022-06-20T12:44:35)
00:00:00.505 WIF: Connecting to AP1 ******************** Channel 6 BSSId 1C:ED:6F:0F:B5:24 in mode 11n as tasmota-A822A6-0678...
00:00:03.759 WIF: Connected
00:00:04.013 HTP: Web server active on tasmota-A822A6-0678 with IP address 192.168.178.77
19:42:11.041 MQT: Attempting connection...
19:42:11.075 MQT: Connected
19:42:11.078 MQT: tele/tasmota_A822A6/LWT = Online (retained)
19:42:11.080 MQT: cmnd/tasmota_A822A6/POWER =
19:42:11.086 MQT: tele/tasmota_A822A6/INFO1 = {"Info1":{"Module":"Generic","Version":"12.0.2(sensors)","FallbackTopic":"cmnd/DVES_A822A6_fb/","GroupTopic":"cmnd/tasmotas/"}}
19:42:11.096 MQT: tele/tasmota_A822A6/INFO2 = {"Info2":{"WebServerMode":"Admin","Hostname":"tasmota-A822A6-0678","IPAddress":"192.168.178.77"}}
19:42:11.109 MQT: tele/tasmota_A822A6/INFO3 = {"Info3":{"RestartReason":"Software/System restart","BootCount":4}}
19:42:12.458 QPC: Reset
19:42:15.454 MQT: tele/tasmota_A822A6/STATE = {"Time":"2022-07-23T19:42:15","Uptime":"0T00:00:11","UptimeSec":11,"Heap":23,"SleepMode":"Dynamic","Sleep":50,"LoadAvg":26,"MqttCount":1,"Wifi":{"AP":1,"SSId":"*****************","BSSId":"1C:ED:6F:0F:B5:24","Channel":6,"Mode":"11n","RSSI":46,"Signal":-77,"LinkCount":1,"Downtime":"0T00:00:05"}}

Op zaterdag 23 juli 2022 om 20:09:03 UTC+2 schreef knowles...@gmail.com:

billy jack newman

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Jul 23, 2022, 2:49:22 PM7/23/22

to Menno Bakker, TasmotaUsers

https://www.google.com/search?q=max6675+tasmota+spi&sxsrf=ALiCzsbVqiv7T200zsGbQakrN6z7s3j7tA%3A1658601957540&ei=5UHcYui7IIGw0PEP3bS0SA&oq=max6675+tasmota+spi&gs_lcp=ChNtb2JpbGUtZ3dzLXdpei1zZXJwEAMyBQghEKABMgUIIRCgATIFCCEQoAE6BwgAEEcQsAM6BggAEB4QFjoFCAAQhgM6BQghEKsCSgQIQRgAUIkIWK4SYNIWaAFwAXgAgAG3AogB6wSSAQcxLjIuMC4xmAEAoAEByAEIwAEB&sclient=mobile-gws-wiz-serp#fpstate=ive&vld=cid:a57fcca6,vid:sS5apP9vqak,st:0

Watch this video it will help, did you ensure you added the SPI files in bin file

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Menno Bakker

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Jul 23, 2022, 2:56:30 PM7/23/22

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You mean the Robojax video on Youtube?

He uses an Arduino sketch, not Tasmota, so I don't see the relevance to my endeavours.

What do you mean by adding SPI files in bin file?

What are SPI files? Doesn't de tasmota-sensors-bin know how to do SPI?

Op zaterdag 23 juli 2022 om 20:49:22 UTC+2 schreef billyj...@gmail.com:

Philip Knowles

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Jul 23, 2022, 5:04:52 PM7/23/22

to Menno Bakker, TasmotaUsers

Also have you setoption94 1?

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Menno Bakker

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Jul 23, 2022, 5:24:24 PM7/23/22

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Yes, I also used setoption94 1,

And tried with a NodeMCU and differnt GPIO's for CS, but still no luck.

Op zaterdag 23 juli 2022 om 23:04:52 UTC+2 schreef knowles...@gmail.com:

billy jack

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Jul 23, 2022, 6:57:21 PM7/23/22

to Menno Bakker, TasmotaUsers

Make sure you are using these ports. This is from Tasmota’s page.

To view this discussion on the web, visit https://groups.google.com/d/msgid/sonoffusers/de68de1e-8991-49e2-a788-7e699c4a6209n%40googlegroups.com.

SPIGPIO.PNG

billy jack newman

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Jul 23, 2022, 7:39:41 PM7/23/22

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Philip Knowles

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Jul 24, 2022, 2:49:40 AM7/24/22

to billy jack newman, TasmotaUsers

He said he was in the first post (but was using the 'D' notation not GPIO).

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Sent: Sunday, July 24, 2022 12:39:41 AM
To: TasmotaUsers <sonof...@googlegroups.com>

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Menno Bakker

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Jul 24, 2022, 7:55:15 AM7/24/22

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Yes, if the information I found on the web is reliable, for the Wemos D1 D6 = GPIO12 =MISO and D5 = GPIO14 = SCLK

That is how it is connected.

Op zondag 24 juli 2022 om 08:49:40 UTC+2 schreef knowles...@gmail.com:

billy jack newman

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Jul 24, 2022, 8:00:25 AM7/24/22

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Where is the mosi connected?

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Menno Bakker

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Jul 24, 2022, 8:04:30 AM7/24/22

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There is no MOSI.

This module has five connections: GND, VCC, SCK, CS, SO.

In that order and with these abbreviations.

I am assuming:

GND = ground

VCC = 5 V

SCK = SCLK

CS = CS

SO = MISO

Op zondag 24 juli 2022 om 14:00:25 UTC+2 schreef billyj...@gmail.com:

Philip Knowles

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Jul 24, 2022, 12:30:29 PM7/24/22

to Menno Bakker, TasmotaUsers

I would connect to 3V3 rather than 5V - not saying that’s the issue but ESP8266 isn’t 5V tolerant on its inputs

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From: Menno Bakker
Sent: 24 July 2022 13:04
To: TasmotaUsers
Subject: Re: MAX6675 thermocouple not working

There is no MOSI.

This module has five connections: GND, VCC, SCK, CS, SO.

In that order and with these abbreviations.

I am assuming:

GND = ground

VCC = 5 V

SCK = SCLK

CS = CS

SO = MISO

Op zondag 24 juli 2022 om 14:00:25 UTC+2 schreef billyj...@gmail.com:

Where is the mosi connected?

On Sun, Jul 24, 2022, 4:55 AM Menno Bakker <mlab...@gmail.com> wrote:

Yes, if the information I found on the web is reliable, for the Wemos D1 D6 = GPIO12 =MISO and D5 = GPIO14 = SCLK
That is how it is connected.

Op zondag 24 juli 2022 om 08:49:40 UTC+2 schreef knowles...@gmail.com:

He said he was in the first post (but was using the 'D' notation not GPIO).

Get Outlook for Android

From: sonof...@googlegroups.com <sonof...@googlegroups.com> on behalf of billy jack newman <billyj...@gmail.com>
Sent: Sunday, July 24, 2022 12:39:41 AM
To: TasmotaUsers <sonof...@googlegroups.com>

Subject: Re: MAX6675 thermocouple not working

To view this discussion on the web, visit https://groups.google.com/d/msgid/sonoffusers/06ce1394-5d14-4f85-8407-e92eb5b4a0b1n%40googlegroups.com.

Menno Bakker

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Jul 24, 2022, 1:54:00 PM7/24/22

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Just to be sure, I tried the example sketch for the Max6675 library on one of the D1 Mini's and it is working with this pinout.

So either I am doing something wrong in setting up Tasmota, or there is something wrong with/in Tasmota itself.

(Most likely the former, as I am quite new to Tasmota)

I think I have ruled out all other points of failure by now.

EDIT: had not sent this message yet: the Arduino sketch works at 5V at Vcc. Just to make sure I am now trying 3V3: still does not work in Tasmota.

Op zondag 24 juli 2022 om 14:04:30 UTC+2 schreef Menno Bakker:

Philip Knowles

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Jul 24, 2022, 2:23:12 PM7/24/22

to Menno Bakker, TasmotaUsers

Can you send a screenshot of the Module Configuration page?

Configuration>Configure Module

and this page

Configure>Configure Other

Sent from Mail for Windows

From: Menno Bakker
Sent: 24 July 2022 18:54
To: TasmotaUsers
Subject: Re: MAX6675 thermocouple not working

Just to be sure, I tried the example sketch for the Max6675 library on one of the D1 Mini's and it is working with this pinout.

So either I am doing something wrong in setting up Tasmota, or there is something wrong with/in Tasmota itself.

(Most likely the former, as I am quite new to Tasmota)

I think I have ruled out all other points of failure by now.

EDIT: had not sent this message yet: the Arduino sketch works at 5V at Vcc. Just to make sure I am now trying 3V3: still does not work in Tasmota.

Op zondag 24 juli 2022 om 14:04:30 UTC+2 schreef Menno Bakker:

There is no MOSI.
This module has five connections: GND, VCC, SCK, CS, SO.
In that order and with these abbreviations.
I am assuming:
GND = ground
VCC = 5 V
SCK = SCLK
CS = CS
SO = MISO
Op zondag 24 juli 2022 om 14:00:25 UTC+2 schreef billyj...@gmail.com:

Where is the mosi connected?

On Sun, Jul 24, 2022, 4:55 AM Menno Bakker <mlab..@gmail.com> wrote:

Yes, if the information I found on the web is reliable, for the Wemos D1 D6 = GPIO12 =MISO and D5 = GPIO14 = SCLK
That is how it is connected.

Op zondag 24 juli 2022 om 08:49:40 UTC+2 schreef knowles...@gmail.com:

He said he was in the first post (but was using the 'D' notation not GPIO).

Get Outlook for Android

From: sonof...@googlegroups.com <sonof...@googlegroups.com> on behalf of billy jack newman <billyj...@gmail.com>
Sent: Sunday, July 24, 2022 12:39:41 AM
To: TasmotaUsers <sonof...@googlegroups.com>

Subject: Re: MAX6675 thermocouple not working

To view this discussion on the web, visit https://groups.google.com/d/msgid/sonoffusers/a67a12a1-8f4f-4336-9dc4-f264794cbcc4n%40googlegroups.com.

Menno Bakker

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Jul 24, 2022, 2:32:06 PM7/24/22

to TasmotaUsers

Another thing I tried was defining a MOSI GPIO, even if the module does not have MOSI.

Op zondag 24 juli 2022 om 20:23:12 UTC+2 schreef.@gmail.com:

billy jack newman

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Jul 24, 2022, 2:41:10 PM7/24/22

to Philip Knowles, Menno Bakker, TasmotaUsers

I belive your correct on that, a step down register may be needed, or use a max31865 for the rtd temp sensor, I have used them with arduino and raspberry pi, but not with the esp8266, I switched to Dallas one wire.

To view this discussion on the web, visit https://groups.google.com/d/msgid/sonoffusers/32D075A0-4392-466B-A1E5-AEAA0844DA3C%40hxcore.ol.

Philip Knowles

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Jul 24, 2022, 2:52:43 PM7/24/22

to Menno Bakker, TasmotaUsers

It should definitely be 3V3.

I think the issue is using Software SPI. I’d try MX31855CS, MX31855 CLK M31855 DO.

Regards

Phil K

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From: Menno Bakker
Sent: 24 July 2022 19:32
To: TasmotaUsers
Subject: Re: MAX6675 thermocouple not working

Another thing I tried was defining a MOSI GPIO, even if the module does not have MOSI.

Op zondag 24 juli 2022 om 20:23:12 UTC+2 schreef.@gmail.com:

Can you send a screenshot of the Module Configuration page?
Configuration>Configure Module
and this page
Configure>Configure Other

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Menno Bakker

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Jul 24, 2022, 2:52:49 PM7/24/22

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Maybe I was not clear enough. I tested the module with an Arduino Uno and an example sketch and it worked.

I tested the module on the Wemos Mini D1, which is ESP8266, on 5 Volts with a library example sketch and it worked.

So the issue is apparently not in the hardware, but in Tasmota.

(I might have to start looking at the newer releases of ESPEasy, but I've never been able to flash any of the newer releases.

All my Domoticz stuff is stuck at R147, which does not support the Max6675)

Op zondag 24 juli 2022 om 20:41:10 UTC+2 schreef billyj...@gmail.com:

Philip Knowles

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Jul 24, 2022, 2:55:58 PM7/24/22

to Menno Bakker, TasmotaUsers

Just because it works doesn’t mean that you should permanently connect a 5V input into a 3V3 device when the breakout board will work on 3V3 anyway.

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Menno Bakker

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Jul 24, 2022, 2:56:41 PM7/24/22

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THAT'S IT!

It works now! Off to the barbecue it is ;-)

Many many many thanks for the help & patience!

Op zondag 24 juli 2022 om 20:52:43 UTC+2 schreef knowles...@gmail.com:

Philip Knowles

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Jul 24, 2022, 2:57:40 PM7/24/22

to Menno Bakker, TasmotaUsers

👍

Sent from Mail for Windows

From: Menno Bakker
Sent: 24 July 2022 19:56
To: TasmotaUsers
Subject: Re: MAX6675 thermocouple not working

THAT'S IT!

It works now! Off to the barbecue it is ;-)

Many many many thanks for the help & patience!

Op zondag 24 juli 2022 om 20:52:43 UTC+2 schreef knowles...@gmail.com:

It should definitely be 3V3.

I think the issue is using Software SPI. I’d try MX31855CS, MX31855 CLK M31855 DO.

Regards

Phil K

Sent from Mail for Windows

From: Menno Bakker
Sent: 24 July 2022 19:32
To: TasmotaUsers
Subject: Re: MAX6675 thermocouple not working

Another thing I tried was defining a MOSI GPIO, even if the module does not have MOSI.

Op zondag 24 juli 2022 om 20:23:12 UTC+2 schreef.@gmail.com:
Can you send a screenshot of the Module Configuration page?
Configuration>Configure Module
and this page
Configure>Configure Other

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Menno Bakker

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Jul 24, 2022, 3:06:21 PM7/24/22

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(And it is and will stay on 3,3 Volts now)

Op zondag 24 juli 2022 om 20:57:40 UTC+2 schreef knowles...@gmail.com:

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