[SOLVED] [Moved] spi,spcr,spdr, at89s8252

[debabrta kar]

hi i working on spi protocol using at89s8252 ...i want to know what is th role of spcr and spdr...i mean what is the function of spi controle register and spi data register and what is their effect during and after spi transmission ...i have read the datasheet of at89s8252 and some pdfs os spi protocol....so plz help me out..thanx in advance

 

[debabrta kar]

Re: spi,spcr,spdr, at89s8252

also give sum idea how to visualise the spdr value in tool...because when i am debugingthe code in keil-2 spdr value is not showing plz help me about this......

 

[kgavionics]

hi i use only microchip
basically, to use spi you have to configure two register SSPSTAT and SSPCON.SSPCON register is used to set the spi mode if either slave or master, the sampling, the rising or the falling edge clock...etc
The SSPSTAT register is used to check if the data was sent or not.pretty easy in case of pic microntroller.
i did a little project with assembly,you can find it here
https://www.edaboard.com/threads/293925/

 

[debabrta kar]

Re: spi,spcr,spdr, at89s8252

yes sir thank and its good that u r a expert...plz help me how to visualize the spdr register value in tool of keil -2 when m debuging my code....i mean how to visualize the data soterd in spdr register ..

 

[kgavionics]

Re: spi,spcr,spdr, at89s8252

yes sir thank and its good that u r a expert...plz help me how to visualize the spdr register value in tool of keil -2 when m debuging my code....i mean how to visualize the data soterd in spdr register ..

i'm very sorry,because i only know Microchip micro-controller, i don't have any clue about Atmega.

 

[debabrta kar]

ok sir thank you......plz any1 who have worked on at89s8252 plz suggest me...............

 

[mathespbe]

SPCR is nothing but to set SPI configuration as the bits available. And SPDR is used to write Tx data and read Rx data in SPI

 

[debabrta kar]

yes sir i know but how to visualize value of SPDR in tool...........

 

[mathespbe]

What tool you are using? And you can view it during the debugging on a register window...

 

[debabrta kar]

i am using keil-2 and in debugging the spdr reg value is not showing...............

 

[mathespbe]

The SPDR register is a read sensitive type. So you can't see it on Reg window. Instead you can read the Rx data through a local variable by read it...
i.e tmp = SPDR;

 

[debabrta kar]

actually i am using assembly langugage so help me how to read it...

 

[mathespbe]

I don't know the exact Assembly programming. You could move the SFR--> SPDR to a general purpose register and watch it on your tool. If it's in C program i can help you...