Need Urgent help ! , C++ code to Initialize ports on 8051 microcon

Replies

• 

  Harshad Italiya

  What is the Requirement of your Ports means in input mode output mode or QB mode??
• 

  Harshad Italiya

  Dear By Default all ports are in INPUT mode
  
  Write...
  If you want just initialization then this is enough...
  P0 = 0x00; // Port 0 in input mode
  P0 = 0xFF; // Port 0 in Output mode..
  
  if you want to Toggle LED at Specific pin than
  
  led = P0^1; //Port 0 pin1 assign as led
  
  now according to led variable LED will toggle.
  
  
  Can please tell me where is the problem i think your initialization is Ok !!
• 

  JAIHO

  Here's the schematics of "what the company will use this chip for " .
  I just scanned and resized it.I am not sure if I need input ports or output ports or QB...??
  #-Link-Snipped-#
  
  
  The initialization is ok ? But the code I have only looks like it's dealing with Port0 Only !!
  How do I Initialize Port1 ( 8 pins ) and Port 2 ( 2 pins ) , with regards to the design requirements ??
• 

  Harshad Italiya

  You can initialize all port by same manner..
  
  P1= 0x00; input only
  P2= 0x00; input only
  
  and yes if you want to initialize only one or two pin then set them to one and remaining pins should set to zero..
  
  
  Which controller you are using?
• 

  JAIHO

  The controller , I think , we will be using , is a C8051F330 GM
  
  PDF ( page 120 )
  So is this all I need to do to initialize the ports?
  P0= 0x00; input
  P1= 0x00; input
  P2= 0x00; input
  
  
  Are all the ports are supposed to be Input or some Output and some Input ? ? and also , do I need to toggle an LED or not?
  Where can I get this information from? I was looking at the schematics and it looks like there are arrows going- in as well as arrows going- out?
• 

  Harshad Italiya

  As per your Circuit Diagram i conclude that...
  
  Port 0 is in QB which is in QB by Default so no need to Initialize it
  Port 1 is also in QB cause there is SPI communicate with Controller
  Port 2 as Output.
  
  i can give you value but before that i have to understood the circuit working
• 

  Harshad Italiya

  Dear JAIHO,
  
  i had just gone through your C8051F33 datasheet..
  as per the description given on the page 121 we have to set
  
  P0MDIN P0MDOUT P0SKIP ---- For Port 0
  and same for all port.... for the value which we will load in That SFR i have to Understood the Working of your Circuit then and then i can give you that valur so it is better that you please first understood the circuit that what is the Function of each pin by that manner you are aware with the possible state of that pin and form that set the SFR i had written above for all port..
  
  Hop this will helps you..
• 

  JAIHO

  ok, You are a very helpful person. I am sure everyone here feel the same way. By the way, do you mean Serial peripheral interface by SPI, and what does Qb stands for?
• 

  Harshad Italiya

  QB is Quasi Bidirectional in this mode Post configured as input as well as output.
  
  
  PS:- We are Crazyengineers Cheers JAIHO.
  Hop you will get your Solution please try to Run and debug this will also helps you. 😉
• 

  JAIHO

  wait - haha , so is this what you think I need to understand first and also I should understand the possible state of the following pins??
  p0.1 - Pwr div
  p0.6 - Pwr En (enable)
  p0.4 - Ext_ voltage
  p0.3 - Motion
  p0.2 - Btn_1
  p0.5 - In Ignition
  p0.7 - SPI SCK
  p1.0 - SPI MISO
  p1.1 - SPI MISO
  p1.2 - SPI SEL
  
  p1.3 - 12C SDA
  p1.4 - 12C SCL
  p1.6 - LED 1
  p1.7 - VBATT/2
  p1.5 - 2.8V IO_Enable
  p2.0 - C2D
  RST/C2CK
  VDD ( +2.8 Volts )
  GND
  
  Can you tell me details on what is it that I need to understand about these pins?
  for example :- One of the things i need to understand is , if it is a push pull pin right?
• 

  Harshad Italiya

  Yes thats what i am asking.. get the possibilities and according to them configure the Port suppose you had connected LED at P1.6 so configure it as Output only.. so on..
• 

  JAIHO

  Do you know what a "Crossbar" is ? Is that where all the connections come into ? Why do we need to set it ?
  Also my understanding of a push pull pin is that , when it's Digital "1" it's active high and the line is pulled down . meaning anything that's functioning is stopped for a little while.
  
  When it's Digital "0" , it's active low and the line is pulled down , meaning everything is back to functioning normally?
  
  Am i correct in my understanding?