RANDOM - always the same result

[Acetronics2]

Hi,Flotul

1) Read carefully the manual : there must be a SEED for the random function ... if always the same ... always the same result !!!

2) a little SEARCH would be THE THING to do ... good surprise for you !!!

Alain

[flotulopex]

Bonjour Alain,

Thanks...

I just found a way to make it work.

I changed my code and put R_V0 = rvalue & $03. But, to be honest, I don't understand why it works now.

Before opening this thread, I read lots of other threads about this subject. I've also been reading the Compiler's manual. I read this "Var is used both as the seed and to store the result" but my english is to poor and I don't understand the correct meaning of the word "seed" (graine - in french) here.

Could you explain this command in other words please?

[mister_e]

Kind of 'conjugaison du verbe voir => see, seed'.

Qu'est-ce qui a déja été vue, sortie, choisi, sélectionné.

[flotulopex]

j'ai l'air un peu c.. avec ma "graine"

a) So, when the statement is RANDOM RandomVar, the "output" value will be stored in RandomVar, no?

b) R_V0 = rvalue & $03 will keep only the 4 LSB of the result, no?

c) still don't understand why my code in post#1 doesn't work. Must I specify it is in a loop? It is and doesn't work.

[mister_e]

j'ai l'air un peu c.. avec ma "graine"

LMAO you don't want to know the meaning of the Quebec expression 'Graine'

a) So, when the statement is RANDOM RandomVar, the "output" value will be stored in RandomVar, no?

Indeed

b) R_V0 = rvalue & $03 will keep only the 4 LSB of the result, no?

Nope, 3=%00000011 so only the 2 LSBs

c) still don't understand why my code in post#1 doesn't work. Must I specify it is in a loop? It is and doesn't work.

I guess you should use something like
rvalue=R_V0 before using Random again...

[flotulopex]

I have some kind of idea...

I'm coming over to CANADA next winter for holidays. Let me know which words, I European, shouldn't use

I thought the "&" operator would keep (isolate) only bits 0-3 of "Value" but I was wrong. For the fours LSB, I should have written $0F.

What is then this "& $03" for?

As you suggested, I modified my code as (I've added the "Value = R_V0" in le loop):

Value Var WORD
Store_MEM:
FOR Counter = 0 to 20
   RANDOM Value
   R_V0 = (value & $03)
   IF Mem_L > 3 THEN READ Mem_L - 3, R_V1 'Do not allow more than 3 same # in a row
   IF R_V1 = R_V0 THEN STORE_MEM
   WRITE Mem_L, R_V0
   Mem_L = Mem_L + 1
   Value = R_V0
NEXT

Nevertheless, I always get the same number sequence over again.

[flotulopex]

Is this really RANDOM?

I've been checking the sequence over and over again with 50 "random" generated numbers in a row.

The result is an exact same complete sequence everytime I power-up my PIC.

Anyone any clue?