serial communication between microcontroller 8051 and matlab

i want to send information through matlab to 8051. to control the speed of motor.if any key is pressed the speed should up. and other key for down.

plzzzzzzzzzzzz help. i really need.

I am working through pwm. so if high pulse occur so motor get up,and if low pulse then motor speed down.

so I did this with external internpt in interrupt, so its working but with matlab its not working. im using imtool for this purpose

to understand the key i use sbuf reg in 8051,

org 0

mov tmod,#20h
mov th1,#-3
mov scon,#50h
setb tr1
here: jnb ri,here
mov a,sbuf
cjne a,#'a',n1
setb p2.0
acall delay
clr ri
sjmp here
n1: clr p2.0
acall delay
clr ri
sjmp here

delay:
mov r2,#255
h7: mov r3,#250
h8: djnz r3,h8
djnz r2,h7
ret

end

now you can understand my program easily. what will happen.

I am using keyboard

now you can get my all point.

please help

Answer 1

[Walter Roberson]

What serial port characteristics do you require for this interface?

What command does the microcontroller need in order to increase the speed? What command does the microcontroller need to decrease the speed?

How were you planning to notice key presses and decide which key was pressed?

When you say "key" do you mean keyboard, or do you want it to be mouse controllable as well (or instead)?

If you do mean keyboard, then will there be a graphics window also available, or does this need to work even if there is no graphics display available?

[muhammad yasir]

i gave you answer of your question.u can check it.

[Walter Roberson]

I caught that when the 8051 receives 'a' it does something, but you need to write out in words:

What speed (baud rate) and parity will you use to communicate between MATLAB and the 8051?

What command needs to be sent from MATLAB to trigger the microcontroller to increase or decrease the speed?

How were you planning to notice and differentiate key presses in MATLAB ?

Will there be a graphics interface available in MATLAB or does this need to work even when there is no graphics interface?

[muhammad yasir]

baud rate 9600

you can see that when "a" is not equal so clr. if "a" so make it high p2.0 which is connect to motor.

i m using tmtool to send mydata.

i dont know abt graphics interface.

[Walter Roberson]

With regards to the particular characters sent to the microcontroller, you should assume that this is a MATLAB newsgroup and that I might not know the 8051 assembly language that you are using.

I also do not have the Test and Measurement Toolbox, and as you had not previously mentioned that you were using that, I had no way of guessing it.

If you don't know about the graphics interface, then you had better find out, because the *supported* ways of reading individual keys from a keyboard require using the graphics interface.

When you have finished assuming that we will "just know" things you have failed to mention despite having been asked about them, read these reference pages:

http://www.mathworks.com/help/toolbox/instrument/serial.html

http://www.mathworks.com/help/toolbox/instrument/fopen.html

http://www.mathworks.com/help/toolbox/instrument/fread.html

http://www.mathworks.com/help/toolbox/instrument/fwrite.html

http://www.mathworks.com/help/techdoc/ref/figure_props.html

(KeyPressFcn)

http://www.mathworks.com/help/techdoc/ref/uicontrol_props.html#bqxoim8

http://www.mathworks.com/help/techdoc/ref/uicontrol_props.html#bqxoijj

http://www.mathworks.com/help/techdoc/ref/uicontrol.html

(Specifying the uicontrol style)

Answer 2

[kanan baheti]

can u post ur matlab prog here?????

[muhammad yasir]

i didnt make any program.i used tmtool to send my data.

is this procedure is correct.plz check it and tell me.

plz help me. i m not getting my result.

Answer 3

[muhammad yasir]

plz help me. i m not getting my result. i need urgent.

[Walter Roberson]

If you had answered the questions put to you without a 1 1/2 day delay, would the situation still be "urgent" ?

If you want my attention "urgently" on a Sunday afternoon, you can book my time *in advance*, and you can pay my incremental costs for having to run my household errands during the week.

Answer 4

[Stephen Justin]

you need to changes the hexadecimal values are properly prefixed with 0x, the th1 is set to the proper value for 9600 baud rate -3, scon is set to the proper value for serial communication 0x50

[Walter Roberson]

@Stephen Justin

The code they posted back then uses

mov scon,#50h

I would have expected that the "h" suffix would indicate hexadecimal, and so 0x50 would not be required ?