Do I need extra hardware for Peripherals mentioned in Datasheet?

Thread Starter

Abdul Salam

Joined Jul 15, 2017
10
May be it is a silly question but I have seen many examples on web (!not) using RS232 (MAX232) while PIC MCU (PIC16F887) Datasheet says it has UART builtin.

Do I really need RS232 to communicate with external hardware (say PC)?
 

OBW0549

Joined Mar 2, 2015
3,566
May be it is a silly question but I have seen many examples on web (!not) using RS232 (MAX232) while PIC MCU (PIC16F887) Datasheet says it has UART builtin.

Do I really need RS232 to communicate with external hardware (say PC)?
Most PICs have a UART built-in, but they don't provide the TTL-to-RS232 level translation (i.e., interfacing 0-5V logic levels to ±12V RS232 levels). If you're going to communicate with a PC you'll need to use a MAX232 or equivalent (for a PC with a serial port) or a USB-to-TTL-serial cable (or chip) for a PC with USB.
 

Thread Starter

Abdul Salam

Joined Jul 15, 2017
10
Most PICs have a UART built-in, but they don't provide the TTL-to-RS232 level translation (i.e., interfacing 0-5V logic levels to ±12V RS232 levels). If you're going to communicate with a PC you'll need to use a MAX232 or equivalent (for a PC with a serial port) or a USB-to-TTL-serial cable (or chip) for a PC with USB.
Thank you for super fast help

The PIC UART signals are 0-5V. Standard RS232 voltages are bipolar and usually higher than 5V.
Read this: https://www.sparkfun.com/tutorials/215
It explains well esp questions came in mind after reading first reply.

Thank you AlbertHall
 
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