Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

regarding RS485 problem(very urgent)

Status
Not open for further replies.

kovendanj

Newbie level 4
Joined
May 25, 2009
Messages
5
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,318
Hi ,
I was communicating with master slave concept for RS485.

If i communicate with the one master and one slave it is woking good .
But if i connect one master and two slaves , the second slave gets hanged, i.e display displays some wrong character.I had connected the second slave as only hardware(no query is sent to it from master).


The RS 485 ckt is a standard one which i got from net only. I will also attach it.
In the pdf page no 181 , the ckt is there. Here master is a 3.3 v PXA 270 processor (Embedded wince OS)and slaves are 5v 8051 microcontrollers .

I dont know where the problem is situated . Whether it is in hardware or software.

Pl help me . I am doing this for more than 1 month.

Very urgent
 

IanP

Advanced Member level 5
Joined
Oct 5, 2004
Messages
7,942
Helped
2,309
Reputation
4,620
Reaction score
531
Trophy points
1,393
Location
West Coast
Activity points
66,459
The hardware looks all right, it has to be a software bug(s) in the slaves ..

Rgds,
IanP
 

kovendanj

Newbie level 4
Joined
May 25, 2009
Messages
5
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,318
Dear sir ,

Here with i attach the code for two slaves , I am unable to find the error in the slave code.

Pl see the program and check it , and revert me if there is any problem.

Both the slaves works correctly when they were connected as one to one i.e one master to one slave

Plz help , i am doing this for 1 month , pl help ver urgent
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top