nterface an 8-bit DAC with 8051 (P0) to drive a small motor

[fafu]

Two programs need HELP!

Hi guys,
I'm new here.
I have two problems need some help.

First problem
Interface an 8-bit DAC with 8051 (P0) to drive a small DC motor (12V), connect 3 pushbottons as INC, DEC & Enter to set the value (SP) to RAM location 30H.
Write a program for the following tasks:
1) INC/DEC switches can set a vaule (SP) to RAM location 30H.
2) As Enter key is pressed, the 8051 should send the same value from 30H to DAC to drive the DC motor.
(Block Diagram + Circuit Diagram + Program)

Second problem
Interface a Temperature sensor (Lm35) with 8051 using ADC (P0) use 3 Pushbottons to set a value (SP).
Use RAM location 30H to save the temperature set value & 40H to store the actual value (AV) comming from ADC.
Write a program for the following task:
As Enter key is pressed, 8051 will compare the (SP) with (AV) & do the following action:
If AV => SP the Heater OFF
IF AV < SP the Heater ON
(Heater is connected via a relay with P2.7)
(Block Diagram + Circuit Diagram + Program)

:|

 

[Nikunj Tanna]

Re: Two programs need HELP!

For first program

I refer to DAC0808 for 8 bit DAC. Choose IC for DAC with your controller and proceed with datasheets. Make programs for individual for keypads then go with interfacing of DAC.
Refer to old posts of this foru.

As far second program is concern
follow the link. It might give you basic idea.



NIKS