How to send 24 bit data using UART in PIC18F4520

[Harshil3]

Sir i want to send 24 bit data using USART in PIC18F4520.. i m using hi-tech c compliler and Mplab. please sir suggest me how to send data and please give some code for it. i m attaching one file which contains data that i have to send.. please some one help me out...

 

[jayanth.devarayanadurga]

You can send data of any length using USART. Send one character at a time. The data is in excel file. How will you read excel file from microcontroller?

 

[Harshil3]

actually the excel sheet provided is the frame format of different commands. How can I create this frames and save in the controller so that whenever a request is made the corresponding frame can reply

 

[jayanth.devarayanadurga]

I don't have excel installed on my PC. Post the screenshot of the excel files. You will need to create a table but there is limitation depending upon memory of the controller.

 

[AKENAFAB]

Sir i want to send 24 bit data using USART in PIC18F4520.. i m using hi-tech c compliler and Mplab. please sir suggest me how to send data and please give some code for it. i m attaching one file which contains data that i have to send.. please some one help me out...

As ligo says.

Divide your data in 3 parts then use the USART todo send 8 bit packets(data low, mid and high).

That`s the best way or you could use software USART and send the complete 24bit data at once.

 

[Harshil3]

this is the screenshot of one of the frame .....like this frame there many other frames .....so do i need to format this frame in a structure ?

 

[jayanth.devarayanadurga]

Post an example of the your different kind of frame. You need to send data 1 byte at a time. If you post an example of a complete frame then I will write a piece of code to send that frame. On the receiving side you have to collect and store the entire frame in a sting variable and check if data is valid. If data is valid then you can do further actions.

 

[Harshil3]

AA0105006655
here in this example
AA is the start byte
01 is the slave address
05 is the function code
00 is the data
66 is the crc &
55 is the stop byte
in response to this frame the data part will be filled with some data nd will responsed back

 

[jayanth.devarayanadurga]

What is the range for slave address, function code, and data? Can data be > 99?

 

[Harshil3]

each of 8-bits and yes data can be 99 it may vary from 0-255 i.e in hex it will be 00-FF

 

[jayanth.devarayanadurga]

What Compiler you want to use? mikroC PRO? You have to send one byte at a time.

 

[Harshil3]

What Compiler you want to use? mikroC PRO? You have to send one byte at a time.

we are using Hi-Tech C compiler..

 

[jayanth.devarayanadurga]

See UART examples for 8051 and PIC at saeedsolutions.blogspot.com

You have to send data one byte at a time.