Asked
— Edited
Resolved by EEGbiofeedback!
My turn to ask a question for a change
My MMA7455 arrived today but I'm struggling to get them to register anything when connected. Just wondered if I had it connected up right or if I need to do anything extra.
My wires are about 1" long, connected to VCC, ground, SDA and SCL on the MMA and on the EZ-B.
I'm using a simple breakout board which uses the MMA datasheet here.
Schematic of the breakout board is;
Update/Edit: I think I may need to set the CS pin high, i.e. 5v. Is that correct? I don't want to fry the EZ-B or the MMA.
If i am reading the data sheet setting CS high or low just sets the communication protocol. Page 5 table 1 pin 7.
That's how I read it, and CS high puts it in I2C mode (which is what I need), so I assume I need to make CS high?
For some reason I am lacking in the confidence to just go for it although may do later if I get bored.
Rich I have one but don't have it setup at present had similiar issue initially https://synthiam.com/Community/Questions/2320
post #5
Then yes that is where problem is. It's on the other protocol, so I'd set it high. I understand your concern too you are one of the sharpest guys here trust your gut.
Well setting high didn't make any difference. I'll try the pullup resistors when I get chance. I'm also not entirely convinced that my jumper wires are sound (my multimeter leads have been known to play up - I guess I need to buy a new one).
Both modules do the same thing too so I'm assuming it's not a bad module (or I am very unlucky to get 2 bad ones).
I'll have more of a play around later. Have a garden that needs sorting out and since the sun is out (for a change) I'll hit that up in the hopes that forgetting about this will give me that sudden eureka moment.
Yeah i am with you very unlikely to get two bad units. I'll read it again when i get a minute.
OK so I've tried setting the CS high and low but neither seem to work. Added pull up resistors but they didn't seem to make it work.
Anyone have any other ideas?
I haven't forgotten about ya. Its been a long time since I got this deep into electronics. Well college was the last time and I don't think I was paying much attention then either eek