VS1838B remote

[gebillpap]

Once upon a time , there was a brilliant and very helpfull gentleman named Bruce Reynold.
He posted some Infra Red routines for PIC's in PICBASIC at his site Rentron.com which now is lost.
The general idea was to create a routine ,at the encoder ,which lasted in total 26μs and a dutycycle of 25% toggling a port bit on and off thus having a frequency of 38Khz.
I kept a copy and maybe you can get an idea

PROCESSOR 12c508
#include "p12c508.inc"
__CONFIG _MCLRE_OFF & _CP_OFF & _WDT_OFF & _IntRC_OSC
#DEFINE PORT B'11111101'
MOVF OSCCAL
MOVLW PORT
TRIS GPIO

BEGIN
BCF GPIO, 1 ;1uS
NOP ;2uS each nop is 1uS long
NOP ;3uS
NOP ;4uS
NOP ;5uS
NOP ;6uS
NOP ;7uS
NOP ;8uS
NOP ;9uS
NOP ;10uS
NOP ;11uS
NOP ;12uS
NOP ;13uS
NOP ;14uS
NOP ;15uS
NOP ;16uS
NOP ;17uS
NOP ;18uS
NOP ;19uS low on gpio.0
BSF GPIO, 1 ;1uS Begin HIGH duty cycle
NOP ;2uS
NOP ;3uS
NOP ;4uS
NOP ;5uS
GOTO BEGIN ;2uS (26uS total for 38KHz)
END

I remember that he also had a working example with a pair of pic16f628 for remote control.
Maybe somebody can help further.
Regards

[Michael]

I remember the Rentron stuff -- excellent. Thanks for that code, I'll look into it and play with pulsin. It should be more accurate sounds like.

It's working 98% of the time but alas, that isn't good enough. The goal is a foolproof on/off switch just sensing Ired.
Noise is the problem with those receivers.

[Michael]

Never used pulsin. So if I knew the pulse width of the 38khz signal, I can compare it to a result pulsin gives? I just read something where it says it measures just one pulse, either low or high state and then goes to next instruction? Why a word variable if it just measures once?

I get frustrated with some of the PBP commands. The manual is too vague. Wish for every command they could have done another page just with code examples and an explanation of what's going on. (just me venting).

[Michael]

I found that Rentron code. Wow. It's all there and well commented -- I'll try it out. His comments really spell it out and teach.

[Michael]

Pulsin works great. Heck, I just used the first part of that rentron code and did this with it --
I get a perfect momentary on/off with a bit of needed pause.


Main:
PULSIN PORTB.0,0,Leader ' leader pulse is ~9mS low-going
IF Leader < 850 THEN
LOW PORTB.2
GOTO Main
ENDIF

IF LEADER > 850 THEN
HIGH PORTB.2
PAUSE 300
ENDIF

LEADER = 0
PAUSE 100

GOTO MAIN

[andybarrett1]

Pulsin works great. Heck, I just used the first part of that rentron code and did this with it --
I get a perfect momentary on/off with a bit of needed pause.


Main:
PULSIN PORTB.0,0,Leader ' leader pulse is ~9mS low-going
IF Leader < 850 THEN
LOW PORTB.2
GOTO Main
ENDIF

IF LEADER > 850 THEN
HIGH PORTB.2
PAUSE 300
ENDIF

LEADER = 0
PAUSE 100

GOTO MAIN

Just a question ......Why:-

GOTO Main
ENDIF

I would assume the other way round .....Genuine question. I can never understand software fully :-)

Andy

[mpgmike]

I think it's a method of skipping other IF/THEN options.

It could also be structured with...

IF This THEN
do something
ELSEIF That THEN
do something else
ELSE None of the above
Don't do anything
ENDIF

Only 1 option will be selected, forcing a break from the test once a match is found.