Displaying numbers on 16x2 LCD

A one second(or so), delay in your main while(1) loop is good method.
Also take "init()" out of the while() loop.
As a general rule, any routine with "init" in the name should not be called repeatedly.

You might consider comparing the latest value, to the one already being displayed.
If they are the same,skip writing to the display.

Thanks, I'll try your suggestion. I was considering about refreshing temperature value if there are any changes but I thought it won't help because if changes are rapid the temp value will still blink. Of course I didn't try so maybe it'll work just fine.

Once I took that init() out of the loop, the value didn't blink, however temp values were all over the screen from one line to another.

Added command to while(1) loop and it works fine, no blinking, that was the problem

Could you verify if I am wrong or right understanding this routine.
If read_bit() is 1 (true) then this bit initiates value|=0x01<<i; and if bit is 0, then it doesn't initiate value|=0x01<<i. So as example if value of temperature is: (0000 0111)MSB (11010000)LSB then called read_byte routine will read LSB part bit by bit starting from 0 and 0,0,0,1,0,1,1 and when the bit value is 1 then this bit is moved by i places left creating 11010000 and calling read_byte the second time, routine reads MSB part. What role the 0x01 plays?

unsigned char read_byte(void)
{
unsigned char i;
unsigned char value = 0;
for (i=0;i<8;i++)
{
if(read_bit())
value|=0x01<<i;
delay(6);
}
return(value);

read_bit() tells the state of pin (proabably) when reading data from external device. so if bit is 1 at time and i = 0, it meas first bit is 1 and hence
Value |= 0x01 << i
simplifying:
i = 0 so, 0x01 << 0 = 0x01
value |= 0x01; => value = value | 0x01; => value = 0x00 | 0x01 = 0x01;

so value will have a 0x01 stored in it after execution.

incase the bit is 0 then no need to shift 1 inside value. understand now?

and data stored in value depends on what is being transferred first, LSB or MSB. in this case i guess LSB is transferred first.

Yes, I understand, thanks, even did it on the paper . I didn't know, that at first shifting is executed and only then OR, I thought that everything works successively: first OR and then shifting and that is way I couldn't understand why I can't get the value on the paper. Finally I almost fully understand programming of DS18B20.

You're welcome glad you understood.

Hi, in order not to create new thread, I'll ask here. In C language it is relatively easy to write a routine for receiving string from PC to 8051, however I would like to ask, how it is done in ASM? I know how to send string to PC in ASM, but how to receive it form PC? To send string to pc or lcd it is needed to use for example: text: db "Text to send". But how to do vise versa?

Hi,

I know how to send string to PC in ASM, but how to receive it form PC

You need to write UART reception using Serial Interrupt.


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