Hey, I want to buy a Bluetooth module from aliexpress or something like this, not something like in sparkfun (25$ 
) just a cheap one like 4$ , I have the ZS040 but it is not working to me with my fritzing and code (attached, resistors are 1k each act as voltage divider), so I want to buy a new one, with 4 pins and not 6, is there any one using some good cheap one and could recommend a link?
Untitled.ino (876 Bytes)
If you can't get the six-pin to work, the four-pin won't work either. The cause is likely to be just slack connections or procedure. The divider resistors are wrong, but that isn't fatal.The "ZS-040" applies to the breakout board. The actual module is an HC-05.
You might find the following background notes useful
http://homepages.ihug.com.au/~npyner/Arduino/GUIDE_2BT.pdf
http://homepages.ihug.com.au/~npyner/Arduino/BT_2_WAY.ino
Nick_Pyner:
If you can't get the six-pin to work, the four-pin won't work either. The cause is likely to be just slack connections or procedure. The divider resistors are wrong, but that isn't fatal.The "ZS-040" applies to the breakout board. The actual module is an HC-05.You might find the following background notes useful
http://homepages.ihug.com.au/~npyner/Arduino/GUIDE_2BT.pdf
http://homepages.ihug.com.au/~npyner/Arduino/BT_2_WAY.ino
I have problems reading the fritzing circuit, I don't know why my voltage divider is wrong and I don't know what's wrong..
davidbalas25:
resistors are 1k each act as voltage divider
Running 5v into a divider with 1k resistors will give you 2.5v. You need 3.3v. Use a 1k and a 2k resistor. On reflection, the 2.5v signal that you have at the moment might be fatal after all. Fix that, and you just might find everything else is OK.
Nick_Pyner:
Running 5v into a divider with 1k resistors will give you 2.5v. You need 3.3v. Use a 1k and a 2k resistor. On reflection, the 2.5v signal that you have at the moment might be fatal after all. Fix that, and you just might find everything else is OK.
but I have 2 resistors of 1k in parallel it's like using 2k resistor, isn't it?
No, that makes a 500 ohm resistor. If they are in series, they make a 2k resistor.
Nick_Pyner:
No, that makes a 500 ohm resistor. If they are in series, they make a 2k resistor.
So basically the only thing wrong is the resistor, I have only 220ohm, 1kohm and 10kohm resistors and no place to buy in my country, can I do it that way?
I guess I shouldn't ask what country that might be, but you are on the internet and eBay speaks to everybody.
If you have enough 1k resistors, you can put two in series where the 2k goes, as I said.
If you do not have enough resistors, note that it is possible to get by without using any. I cannot recommend it, but my first bluetooth setup has been running more or less continuously for about three years with no voltage divider and no damage to anything.
