BPM085 Bug or malfunction ?
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BPM085 Bug or malfunction ?

by Sebseb01 on Mon Oct 14, 2013 2:19 am

Hello,

I have connected my "BPM085" to I2C port of Raspberry pi.

It's correctly detected
Code: Select all | TOGGLE FULL SIZE
$ sudo i2cdetect -y 1
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- 77



But if i run Adafruit_BPM085_exemple.py (With hardcoded smbus 1 or with autodetect)
i see :
Code: Select all | TOGGLE FULL SIZE
Error accessing 0x77: Check your I2C address


for debug i also try i2cdump and it works
Code: Select all | TOGGLE FULL SIZE
$ sudo i2cdump -y 1 0x77
No size specified (using byte-data access)
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f    0123456789abcdef
00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    ................
10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    ................
20: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    ................
30: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    ................
40: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    ................
50: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    ................
60: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    ................
70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    ................
80: a5 94 36 18 a9 27 69 a2 53 bc 22 39 fb 4e c6 dd    ??6??'i?S?"9?N??
90: 85 67 60 ee 4d 91 15 7a 00 41 80 00 d4 bd 09 80    ?g`?M??z.A?.????
a0: a5 94 36 18 a9 27 69 a2 53 bc 22 39 fb 4e c6 dd    ??6??'i?S?"9?N??
b0: 85 67 60 ee 4d 91 15 7a 00 41 80 00 d4 bd 09 80    ?g`?M??z.A?.????
c0: 00 00 bc 33 00 00 00 00 00 00 00 10 00 00 00 03    ..?3.......?...?
d0: 55 02 06 00 00 00 00 00 00 00 00 00 00 00 00 00    U??.............
e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    ................
f0: 00 00 00 00 00 00 80 00 00 00 00 00 00 00 00 00    ......?.........


what i make wrong ?

Thanks
--------
Sebseb01
Sebseb01
 
Posts: 2
Joined: Mon Oct 14, 2013 2:03 am

Re: BPM085 Bug or malfunction ?

by Sebseb01 on Mon Oct 14, 2013 3:54 am

More information, number of error message it's not always same.

(debug mode without altitude)
once i see this
Code: Select all | TOGGLE FULL SIZE
$ sudo python Adafruit_BMP085_example.py
DBG: AC1 =   8761
DBG: AC2 =  -1202
DBG: AC3 = -14627
DBG: AC4 =  34151
DBG: AC5 =  24814
DBG: AC6 =  19857
DBG: B1  =   5498
DBG: B2  =     65
DBG: MB  = -32768
DBG: MC  = -11075
DBG: MD  =   2432
DBG: Raw Temp: 0x6B2D (27437)
DBG: Calibrated temperature = 18.500000 C
DBG: Raw Temp: 0x6B32 (27442)
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
DBG: Raw Pressure: 0xF7F7 (-2057)
DBG: X1 = 5743
DBG: X2 = -2775
DBG: B5 = 2968
DBG: True Temperature = 18.60 C
DBG: B6 = -1032
DBG: X1 = 8
DBG: X2 = 605
DBG: X3 = 613
DBG: B3 = 71314
DBG: X1 = 1842
DBG: X2 = 21
DBG: X3 = 466
DBG: B4 = 34636
DBG: B7 = -458568750
DBG: X1 = 1842
DBG: p  = -26480
DBG: X1 = 501
DBG: X2 = 2972
DBG: Pressure = -26026 Pa
Temperature: 18.50 C
Pressure:    -260.26 hPa


and an other time i see this (for exemple)
Code: Select all | TOGGLE FULL SIZE
$ sudo python Adafruit_BMP085_example.py
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
DBG: AC1 =   -257
DBG: AC2 =   -257
DBG: AC3 =   -257
DBG: AC4 =   -257
DBG: AC5 =   -257
DBG: AC6 =   -257
DBG: B1  =   -257
DBG: B2  =   -257
DBG: MB  =   -257
DBG: MC  =   -257
DBG: MD  =   -257
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
DBG: Raw Temp: 0xFEFF (-257)
DBG: Calibrated temperature = 12.800000 C
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
DBG: Raw Temp: 0xFEFF (-257)
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
Error accessing 0x77: Check your I2C address
DBG: Raw Pressure: 0xF7F7 (-2057)
DBG: X1 = 0
DBG: X2 = 2048
DBG: B5 = 2048
DBG: True Temperature = 12.80 C
DBG: B6 = -1952
DBG: X1 = -117
DBG: X2 = 244
DBG: X3 = 127
DBG: B3 = -1802
DBG: X1 = 61
DBG: X2 = -4
DBG: X3 = 14
DBG: B4 = -258
DBG: B7 = -1593750
DBG: X1 = 61
DBG: p  = 12354
DBG: X1 = 106
DBG: X2 = -1387
DBG: Pressure = 12510 Pa
Temperature: 12.80 C
Pressure:    125.10 hPa


(Sorry for my bad English)
Sebseb01
 
Posts: 2
Joined: Mon Oct 14, 2013 2:03 am

Re: BPM085 Bug or malfunction ?

by adafruit_support_bill on Mon Oct 14, 2013 6:11 am

So sometimes it works and other times it does not? That sounds like an intermittent connection. If you post photos of your soldering and how you have everything connected we'll take a look.
User avatar
adafruit_support_bill
 
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Joined: Sat Feb 07, 2009 10:11 am