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Kai Klaas
02/10/06 07:05
Read: 1402 times

#109704 - Recommendations
Responding to: Suresh R's previous message
Suresh said:
I am using a seperate programming device that connects to the computer USB port for programing the micro.
I would like to know how the three lock bits should be programmed.

This must be an option of the programmer software you use. With Atmel's ISP programmer you can open a menu and select what lockbits to set. So, as I don't know your programmer software I cannot give help.

Suresh said:
I want to use 3 decimal keys(each running from 0-9)to set the value instead of using a BCD switch.

I think the both are the same? Both code the number as BCD? Then, both should have four wires which are '1', '2', '4' and '8' and both should have a wire that's called 'common'. This is the one which connects the four switches '1', '2', '4' and '8' to ground. A look at datasheet of decimal key can help.

Suresh said:
The additional instructions are all one machine cycle(12 crystal pulses).
There are 10 additional instructions. So the delay will be 120 clk pulses.
But how, the execution time for a particular instruction is calculated?

I think it was Andy who gave you a link to the original instruction set of 80C51 family. At the beginning of this instruction set there's a table, where each instruction is listed with number of needed bytes and oscillator periods needed to execute.

An example: Instruction 'clr tr0' needs 1 byte and 12 oscillator periods. If your clock frequency is 11.0592MHz, then this instuctions 'consumes' 1 / 11.0592MHz x 12 = 1.085µsec.

By the way, not all instructions need 12 oscillator periods. 'jnz timer_delay' needs 24.

Suresh said:
Also, i would like to know what things need to be studied for writing codes in C or Keil uvision2 (C51 compiler).
what are all the topics i should be knowing.

I'm not very familar with C. I'm doing a lot of EMC and analog stuff, where the micro is only a little part of the project. We have specialized coders, who intensivly work with C. But, if I have to code something, then I'll do it in assembler nearly always. So, somebody else must give you hints.

Suresh said:
i.e., will learning the architecture of a particular micro alone will be enough (or)
should i be proficient with the instruction set also, ..e.t.c.,

You should intensively learn one certain micro, you want to work with in the next future. This could be the AT89S52 for instance, Erik might recommend you the LPC9xx series from philips. Try to become familiar as much as possible with the architecture and the instruction set of this micro.
If you have understood one certain micro in very detail, then it's no longer a problem for you to understand any other. You will probably migrate to several new micros during your career. But whatever micro you work with, you must understand it thoroughly!

Suresh said:
Is using C language preferred in embeddded software development rather than a Assembly Language? If so - why?

This often depends on personal taste. Mahmood for instance is coding everything in C. Others do everything in assembler. Bigger projects with thousand of code lines are difficult to code in assembler. Critical timing issues are difficult to code in C, on the other hand. So, it depends...
Nevertheless, I think it's never a bad idea to learn coding in assembler, because it supports the learning of architecture of micro.


List of 57 messages in thread
Circuit for dispensing unit      Suresh R      01/31/06 05:09      
   1.1 sec monoshot      Abhishek Singh      01/31/06 09:43      
      this thread is apin off from an earlier      Terry Lingle      01/31/06 13:07      
         yes      Steve M. Taylor      01/31/06 13:55      
         timing circuit      Suresh R      02/01/06 04:17      
   Monostable      Andy Neil      01/31/06 12:08      
   Yes.      Steve M. Taylor      01/31/06 13:06      
   Hello All      Suresh R      01/31/06 22:23      
      Description of the "Dispensing Unit"      Andy Neil      02/01/06 00:39      
         using micro      Suresh R      02/02/06 00:25      
            Microcontroller      Andy Neil      02/02/06 01:35      
               Pressure      Steve M. Taylor      02/02/06 03:51      
            What must your circuit can do?      Kai Klaas      02/02/06 07:17      
               0.1 sec      Steve M. Taylor      02/02/06 10:34      
                  but not with a potentiometer      Erik Malund      02/02/06 10:38      
                     Vernier      Steve M. Taylor      02/02/06 13:02      
                        and calibrate it how?      Erik Malund      02/02/06 13:14      
               Precision        Andy Neil      02/02/06 15:13      
                  Sure!      Kai Klaas      02/02/06 16:01      
                     Price      Andy Neil      02/02/06 17:06      
                        Less than 1€      Kai Klaas      02/02/06 20:02      
                           levels of precision      Suresh R      02/03/06 05:01      
                              Please have a look into datasheet!      Kai Klaas      02/03/06 05:57      
                                 somewhere here there is a link      Erik Malund      02/03/06 06:51      
                                    Details?      Kai Klaas      02/03/06 07:17      
                                       I recall that in an earlier thread      Erik Malund      02/03/06 07:20      
                              Ooops.      Steve M. Taylor      02/03/06 09:49      
                              Blown Discharge PIN      Abhishek Singh      02/04/06 19:15      
                                 You can also let the smoke out of the      Terry Lingle      02/04/06 22:37      
                                    limits      Steve M. Taylor      02/05/06 06:13      
                                       dissapation      Terry Lingle      02/05/06 09:45      
                                          There must be a point.      Steve M. Taylor      02/05/06 10:31      
                                             Fusing the bonding wires      Terry Lingle      02/05/06 13:59      
                                                History making      Steve M. Taylor      02/05/06 14:47      
                                                Current limiting      Kai Klaas      02/07/06 06:42      
                                 I do go through      Suresh R      02/07/06 01:50      
            schematic and code      Kai Klaas      02/05/06 19:47      
               codes      Suresh R      02/07/06 00:32      
                  Instruction Description      Andy Neil      02/07/06 04:28      
                     not quite      Erik Malund      02/07/06 06:09      
                        Pedantic      Andy Neil      02/07/06 07:12      
                           is that not the pot calling the kettle b      Erik Malund      02/07/06 07:17      
                              Of course not!      Andy Neil      02/07/06 07:31      
                  Answers      Kai Klaas      02/07/06 07:55      
                     Re: codes and shcematic      Suresh R      02/10/06 03:55      
                        Recommendations      Kai Klaas      02/10/06 07:05      
                           Decimal switches - how to start C      Erik Malund      02/10/06 08:09      
      LM555 pin 2 wired wrong.      Charles Bannister      02/01/06 04:45      
         ... and the LED?      Andy Neil      02/01/06 05:31      
            i'm sure thts not the circuit      Abhishek Singh      02/01/06 06:38      
            Astable??      Kai Klaas      02/01/06 11:46      
               I wondered who'd spot that first...      Andy Neil      02/01/06 12:47      
   Damaged?      Kai Klaas      02/01/06 11:51      
      And Andy's correction      Steve M. Taylor      02/01/06 12:03      
         Absolutely!      Kai Klaas      02/01/06 12:24      
   one shot in the foot      Erik Malund      02/01/06 12:31      
      Need not to work unreliably      Kai Klaas      02/02/06 07:10      

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