RaspberryPi-bmp180 not providing output

#1

I'm using node-red-contrib-brads-i2c-nodes to read temperature and pressure. I also have a python script that works successfully but wanted to try my hand at Node-Red.
I'm new to Node-Red but am frustrated.
Error is: 2/21/2019, 7:26:43 PMnode: 1cd94fa8.b7ae4
msg.payload : string[22] " unrecognized command."
node bmp180 "ready"
node bmp180 output: msg.payload.temperature
I don't know what to send to node bmp180 to read it from the inject node.
It seem that the upstream node are not configured correctly.
Any help would be appreciated.

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#2

If you click on the 1cd94fa8.b7ae4 bit in the debug it should highlight the node that is causing the error.

How have you configured the bmp180 node you are using?

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#3

bmp180: node imput: none
node output: 1. msg.payload.temperature
node output: 2 msg.payload.humidity
topic: temperature
node says "ready"
node function:
msg.payload = msg.payload;
return msg;
node debug:
input: msg.payload
output: msg.payload
i'm kicking off the project by injecting time (hoping is is not used).
1550845445544 unrecognized command. <--- timestamp?
node-red messages:
21 Feb 19:41:52 - [info] [bmp180:bmp180] {"id":"3d9c10af.110338","type":"bmp180","z":"f6294210.397ab8","name":"bmp180","topic":"temperature","presolution":244,"debugMode":true,"x":320,"y":220,"wires":[["ad5994d2.58464","1cd94fa8.b7ae4"],[]],"outputLabels":["msg.payload.temperature","msg.payload.humidity"]}
21 Feb 19:41:52 - [info] [bmp180:BMP180 @ 0x77] node.p_oversampling -> {"timeMs":26,"value":244,"oss":3,"samples":8}
21 Feb 19:41:52 - [info] Started flows
21 Feb 19:41:52 - [info] [bmp180:BMP180 @ 0x77]
bmp180 calibration parameters loaded.
Calibration Address: 0x8889 AC1 -> 0x1e6b (7787)
Calibration Address: 0x8a8b AC2 -> 0x-4ac (-1196)
Calibration Address: 0x8c8d AC3 -> 0x-3990 (-14736)
Calibration Address: 0x8e8f AC4 -> 0x830e (33550)
Calibration Address: 0x9091 AC5 -> 0x5e69 (24169)
Calibration Address: 0x9293 AC6 -> 0x4359 (17241)
Calibration Address: 0x9495 B1 -> 0x157a (5498)
Calibration Address: 0x9697 B2 -> 0x40 (64)
Calibration Address: 0x9899 MB -> 0x-8000 (-32768)
Calibration Address: 0x9a9b MC -> 0x-2b43 (-11075)
Calibration Address: 0x9c9d MD -> 0x980 (2432)
21 Feb 19:41:52 - [info] [bmp180:BMP180 @ 0x77] BMP180 @ 0x77 ready.
21 Feb 19:41:52 - [info] [bmp180:BMP180 @ 0x77] {"topic":"","payload":"1550796112167 unrecognized command.","_msgid":"5365c8bf.9b0268"}
21 Feb 19:41:52 - [info] [debug:1cd94fa8.b7ae4] 1550796112167 unrecognized command.
21 Feb 19:41:52 - [info] [debug:1cd94fa8.b7ae4] 1550796112167 unrecognized command.
node 1cd941a8.b7ae4 is a debug node

Hope this help.

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#4

Looking at the code for that node it seems you need to send it a string "measure" for it to reply correctly - change your inject to send that and see what happens.

From the overall project readme

All nodes use an [ inject ] node to send a string command of 'measure' to initiate sensor measurement based on values set in the config panels of the flow diagram.

But yeah - docs is not his thing... maybe worth raising an issue on the github page for that node to add something to the info for each node - but it's been a while since he touched it.

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#5

dceejay - You're right on. Where is this documented?
2/22/2019, 4:48:39 PMnode: 1cd94fa8.b7ae4bmp180 : msg.payload : Object

object

name: "BMP180 @ 0x77"

timestamp: "2/22/2019, 16:48:38"

Tc: "30.90"

Tf: "87.61"

p: "101814.90"

P: "30.07"

altm: "-40.71"

altf: "-12.41"

Thanks for your help

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#6

It's on the main project page for the node you mentioned

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#7

Ah, yes. I see it now.
Thank you again.
I have soo much to learn.
Chuck

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