{"id":116,"date":"2013-01-31T00:32:29","date_gmt":"2013-01-31T00:32:29","guid":{"rendered":"http:\/\/richardalbritton.wordpress.com\/?p=20"},"modified":"2015-01-15T23:17:51","modified_gmt":"2015-01-15T23:17:51","slug":"i2c-bus-error-with-led-marix-on-raspi","status":"publish","type":"post","link":"https:\/\/www.richa1.com\/RichardAlbritton\/i2c-bus-error-with-led-marix-on-raspi\/","title":{"rendered":"i2c bus error with LED marix on RasPi"},"content":{"rendered":"

This is mostly for myself but I figured I would post it here as well. After putting together and setting up my new 8×8\u00a0bi-color\u00a0LED matrix and i2c\u00a0control\u00a0PCB from Adafruit, I got a script error saying “Error accessing\u00a00x70: Check your\u00a0I2C\u00a0address”. When I run\u00a0sudo i2cdetect -y 0, I get nothing, but the matrix is detected when I run\u00a0sudo i2cdetect -y 1.<\/p>\n

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So\u00a0apparently\u00a0the\u00a0original\u00a0version ran i2c on #0, but now it is on #1. So the test scripts are looking on the wrong bus for the\u00a0device.\u00a0Making\u00a0a change to\u00a0Adafruit_I2C.py to reflect the\u00a0proper\u00a0device bus should fix the issue… I\u00a0guess\u00a0I will find out tonight.<\/p>\n

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Mini 8×8 w\/ Pi not working<\/a><\/h3>\n

\"Post\"<\/a>by\u00a0jamestenglish<\/a><\/strong>\u00a0\u00bb 19 Dec 2012 01:19<\/p>\n

I am trying to get the mini 8×8 LED with backpack working with my Raspberry Pi, but I keep getting the error:
\nError accessing\u00a00x70: Check your\u00a0I2C\u00a0addressI am using the Occidentals 0.2 linux build.Below are pictures of the Soldering, wiring, and console output. If there is any other information I can provide just let me know<\/p>\n

Soldering:
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Re: Mini 8×8 w\/ Pi not working<\/a><\/h3>\n

\"Post\"<\/a>by\u00a0adafruit<\/a><\/strong>\u00a0\u00bb 20 Dec 2012 21:36<\/p>\n

can you check if its using\u00a0i2c\u00a0bus #0 or #1? it should be #0, try hard-coding it in the python script!<\/div>\n
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Re: Mini 8×8 w\/ Pi not working<\/a><\/h3>\n

\"Post\"<\/a>by\u00a0jamestenglish<\/a><\/strong>\u00a0\u00bb 22 Dec 2012 16:17<\/p>\n

I hard coded it in the python script and it seems to work now, thanks!<\/div>\n<\/div>\n
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Re: Mini 8×8 w\/ Pi not working<\/a><\/h3>\n

\"Post\"<\/a>by\u00a0nkane3<\/a><\/strong>\u00a0\u00bb 18 Jan 2013 20:01<\/p>\n

I am have the same exact problem. Except I have a RPi Rev 2. When I run sudo i2cdetect -y 1 it reads 70 and sudo\u00a0i2c\u00a0detect -y 0 is reads nothing. When I run the test code (ex_8x8_pixels.py), I get the same exact problem: Error Accessing\u00a00x70: Check your\u00a0I2Caddress. Im not sure how to hard code it in python. And for my board, should I be using #1? How would I change this?<\/div>\n<\/div>\n
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Re: Mini 8×8 w\/ Pi not working<\/a><\/h3>\n

\"Post\"<\/a>by\u00a0nkane3<\/a><\/strong>\u00a0\u00bb 18 Jan 2013 22:07<\/p>\n

Nevermind I figured it out. For those with the same question, the Revision 2 does use\u00a0I2C\u00a0#1. In order to hard code this, go into Adafruit_I2C.py and uncomment one of the two lines. The lines will say which raspberry pi they correspond to.<\/div>\n<\/div>\n
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Re: Mini 8×8 w\/ Pi not working<\/a><\/h3>\n

\"Post\"<\/a>by\u00a0Awright754<\/a><\/strong>\u00a0\u00bb 19 Jan 2013 15:08<\/p>\n

I have a very similar issue with my 7-Segment display, i run the example script ‘ex_7segment_clock.py’ and get ‘Error accessing\u00a00x70: Check your\u00a0I2C\u00a0address.
\nThe device shows up on i2cdetect as\u00a00x70. I found the line in the scrpit ‘Adafruit_I2C.py’ that i need to make active so i can get my Pi model (I have model B), however i cannot edite the file as its states ‘Errno 13 permission denied’ when i go to save the file.
\nAnyone any ideas what i can do?<\/div>\n<\/div>\n
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Re: Mini 8×8 w\/ Pi not working<\/a><\/h3>\n

\"Post\"<\/a>by\u00a0Awright754<\/a><\/strong>\u00a0\u00bb 19 Jan 2013 15:28<\/p>\n

Got it, just moved all the files i needed into a new folder!<\/div>\n<\/div>\n
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