Hey everybody,
I'm currently using a ITEAD bluetooth shield that has a HC-05 bluetooth module connected to my UNO. My question is what's the difference between software and hardware spi on the device?
any knowledge is appreciated!!
Cheers!
Perhaps you mean software/hardware serial.
Uno has one hardware serial port, pins 0,1 as clearly marked.
Other pins can be used for serial communication by configuring them with extra code - software serial - which enables you to use additional serial devices.
The matter is slightly complicated because the hardware serial is shared with the serial monitor. This is not necessarily a liability, indeed it can be an asset, but it does mean that you cannot upload to Arduino with bluetooth connected.
what's the difference between software and hardware spi on the device?
Which device?
If you mean the UNO, hardware SPI doesn't use anywhere near as much CPU as software SPI and is more reliable.
Pete
Thank you for answering!
So if I use pins 0 and 1 have the transmitting pin hooked up to the receiving pin and vice versa, I should be able to use the serial functions that are equipped with an uno board? Through my reading I have noticed that there is a SoftwareSerial library that I have seen used. Is this the same as the built in serial communication in the arduino library? Any clarification would be appreciated!
kingmigs:
So if I use pins 0 and 1 have the transmitting pin hooked up to the receiving pin and vice versa, I should be able to use the serial functions that are equipped with an uno board?
Yes. That is why they are there.
Through my reading I have noticed that there is a SoftwareSerial library that I have seen used. Is this the same as the built in serial communication in the arduino library?
No, but it serves the same purpose. The Uno has only one serial port. Software serial allows you to use an additional pair of pins as a serial port for when you have two serial devices, say GPS and Bluetooth. Software serial isn't such a good idea, and best avoided.
Note that the serial monitor shares the COM port with pins 0,1, which means you cannot upload programmes with a device connected to hardware serial. This is sharing more of an asset than a liability, but you do need to know about it, and remember to disconnect any device before uploading.