Python and Java on a PIC! I just need a little help...

[jumpjack]

Do you think it is impossible?
I think not.
I actually think we CAN write Python and Java code for PICs!

It's just a matter of getting a python-programmable or java-programmable cellphone able to communicate with a PIC!
There are thousands of cellphones supporting python, and even more supporting java, just look for "pys60" and "j2me".

Connecting them to any PIC should be very easy, and I am currently studying about it: all of these phones have audio headset support, which means they can send and receive audio signals (i.e. voltage signals).

Getting them communicating with a PIC should be just a matter of enabling a PIC to "understand" if the signal is present or not on a pin; a python program on the phone will then "modulate" the sound in a proper way (i.e. you'll have to invent your protocol) to drive the PIC.

I think adding an RC filter to turn sinusoid into constant voltage, and connecting this voltage to a comparator pin in 16f628 should be all we need.

But I need some help to build this proof-of-concept project.

Where could I find a sample source to use comparators on 16f628?
I just want the PIC to light a led upon detecting an analog signal on a pin.

 

[Nigel Goodwin]

Do you think it is impossible?
I think not.
I actually think we CAN write Python and Java code for PICs!

You think completely wrong, your 'idea' is't running Python on PIC, it's running Python on a phone - the PIC would be running assembler as usual.

 

[jumpjack]

You think completely wrong, your 'idea' is't running Python on PIC, it's running Python on a phone - the PIC would be running assembler as usual.

of course, but what's the matter? The result will be I can control the PIC using Python!

 

[Nigel Goodwin]

of course, but what's the matter? The result will be I can control the PIC using Python!

But what would be the point?, and the fact an external device is running Python has no bearing whatsoever.

 

[Torben]

of course, but what's the matter? The result will be I can control the PIC using Python!

You can do that using a PC, a phone, or anything else. This is no different from the phone or PC communicating with any other device which contain a microcontroller--which is pretty much anything you can plug into your PC or phone.

Not to shoot your idea down, but there are already digital interfaces (RS-232, USB, and a bunch of others) for communicating with a PIC or other microcontroller from a higher-level platform using a high-level language. No need to co-opt the audio on a phone to do it.


Torben

 

[jumpjack]

You can do that using a PC, a phone, or anything else. This is no different from the phone or PC communicating with any other device which contain a microcontroller--which is pretty much anything you can plug into your PC or phone.

Not to shoot your idea down, but there are already digital interfaces (RS-232, USB, and a bunch of others) for communicating with a PIC or other microcontroller from a higher-level platform using a high-level language. No need to co-opt the audio on a phone to do it.


Torben

you forgot 3 things:
- a cellphone does not require external power for at least 48 hours, and even if it is being charged, it requires a few watts
- a cellphone can be placed anywhere around rather than on a desktop
- cellphones can receive SMS

 

[jumpjack]

anyway I still didn't receive any answer to my questions...

 

[Torben]

you forgot 3 things:

No, I didn't. For one thing, in the below questions, you focus on the fact that I used the term "PC", which of course was just an example. For another, you're essentially saying that I had knowledge of something you never explained: the need for portability. Your original post was about the possibility of PICs supporting Python using your idea, which is incorrect. You have now veered off onto another topic.

- a cellphone does not require external power for at least 48 hours, and even if it is being charged, it requires a few watts

A well-designed PIC or other µC circuit can easily last that long on battery power too.

- a cellphone can be placed anywhere around rather than on a desktop

This is irrelevant to your original point that the method would mean that PICs support Python in the way you describe. You are simply describing using a high-level language to interface to a lower-level device. The fact that you want to use a cell phone as a cut-rate wireless modem doesn't mean anything in that context.

- cellphones can receive SMS

So can PICs.

It appears that your point was essentially that you can use Python to send SMS messages to a cell phone, which relays the messages in some form to a microcontroller. This is not a new idea.


Torben

 

[Nigel Goodwin]

Phones have a direct interface socket on them, simply connect that to the PIC - Nokia phones are the best documented on the net, so a good choice.

 

[Papabravo]

Let me know which PIC you think you can put a Python or Java interpreter into. I'd be willing to wager that it would be a tough proposition. I'd also like to know which language you think the interpreter would be written in. Arrrrgh....assembly language anyone?

 

[jumpjack]

Ok guys, you don't like my idea and taht's all, but please stop bothering me with "it's an old idea", "you could do it in a better way just buy googling&studying for 3 months", "it's useless", "it's impossible, python can't run on PIC"...

I'll be soon able to drive my PICs by means of a python or java program, and that's all.

 

[Papabravo]

Which PIC do you tink will meet your requirements? That is still the puzzler.

 

[jumpjack]

Which PIC do you tink will meet your requirements? That is still the puzzler.

anyone with analog input or comparator.

 

[philba]

So Jack, why don't you take any pic that works, prototype your idea and report back here. I'd like to see what you come up with.

 

[jumpjack]

So Jack, why don't you take any pic that works, prototype your idea and report back here. I'd like to see what you come up with.

I'm trying. I'm a bit in trouble with 16f628 comparator, but I'll figure it out... I hope.

 

[jumpjack]

Hey, I did it!
Now my PIC gets triggered by an audio tone played by the phone!!

https://it.youtube.com/watch?v=ohD0ucjRHDU

Sorry for very poor quality of video...

This is my silly source:

; PHONE2PIC program
; This program interfaces a cellphone to a pic by means of cellphone
; audio output: upon detecting any signal present on the pin
; connected to the cellphone headset audio output, a led is lit.
;
;
; Just a proof-of-concept: use this source to write a program which allow
; driving an high current relais to be able to drive any equipment by SMS
; (you'll need a proper program running on the cellphone).
;
; ****** Comparatore settings ******
; Comparator pins RA3 to RA0 (4 pins)
; Set comparators mode by settings bits CM2:CM0 in CMCON register:
; CM2:CM0 = 010 : pin RA0 is input, bit C1OUT (bit 6) in CMCON is output, 
; internal Vref is reference voltage.
; Voltage Reference module must be set up by setting VRCON register:
; VRCON = 1010.0110
;         |||| |||'-- VR0 \
;         |||| ||'--- VR1  \
;         |||| |'---- VR2  / Vref = VR*Vdd/24 if Vrr = 1
;         |||| '----- VR3 /  Vref = Vdd/4 + VR*Vdd/32 if Vrr = 0
;         |||'------- n/a
;         ||'-------- Vrr     Set divisions
;         |'--------- VRoe    Send output to RA2 if enabled
;         '---------- VRen    Enable Vref circuit.

  PROCESSOR   16F628A
  RADIX       DEC
  INCLUDE     "P16F628A.INC"
    ;__CONFIG    11110100010000B
; Configuration is:
;   Master Clear pin is disabled (used as input)
;   Code Protection is OFF
;   Watchdog Timer is ON
;   Oscillator is Internal RC
    __config  _MCLRE_OFF & _CP_OFF & _WDT_ON & _INTRC_OSC_NOCLKOUT

  cblock 	0x20 	;start of general purpose registers
		count1 			;used in delay routine
		counta 			;used in delay routine 
		countb 			;used in delay routine
	endc

C1OUTMASK   	Equ b'01000000'		;Comparator1 output bit

  ORG	0x0000
	GOTO	START
	ORG	0x0004
	GOTO	START
    
START
    bcf	STATUS,RP0 ; You must be in Bank 0 to access CMCON.
    movlw	b'00000010'		; enable comparators by setting CM2:CM0 == 010 (internal reference)
;           |||||||'--  \  Set comparator mode:
;           ||||||'---     '010' means "use internal voltage reference
;           |||||'----  /
;           ||||'-----  CIS = 0 => Comp1 input is from RA0
;           |||'------  C1INV: invert Comp1 result (DISABLED)
;           ||'-------  C2INV: invert Comp2 result(DISABLED)
;           |'--------  ****** C1OUT: output of Comp1 ******* <<<=====----
;           '---------  C2OUT: output of Comp2  (NOT USED)    
    movwf	CMCON		      ; Comparator input is RA0.  See 16F628A datasheet section 10.0
    
    
    bsf	STATUS,RP0 ; You must be in Bank 1 to access VRCON.
; ********** Set reference value ********* <<<====----    
    movlw b'10100001'   ; Enable Vref module and set Vref ======== 0110 = 6  => 1/4 Vdd = 0.125 V
;           |||||||'-- VR0 \
;           ||||||'--- VR1  \
;           |||||'---- VR2  / if Vrr = 1:  Vref = VR*Vdd/24 
;           ||||'----- VR3 /  if Vrr = 0:  Vref = Vdd/4 + VR*Vdd/32 
;           |||'------ n/a
;           ||'------- Vrr     Set divisions scale
;           |'-------- VRoe    Send output to RA2 if enabled
;           '--------- VRen    Enable Vref circuit.
    movwf VRCON         ; See 16F628A datasheet section 11.0
    call DELAY ;Time to settle down VREF
    
    
    BSF         STATUS,RP0    ; Bank 1 
    CLRF        TRISB         ; PORT B is output
    BCF         STATUS,RP0    ; Bank 0
    
    

    bcf	STATUS,RP0 ; Must be on Bank 0 to access CMCON (comparator results)
    
L_CHECK    
        CLRWDT
        movf CMCON,w
        andlw C1OUTMASK			      ; check C1OUT bit
        btfsc STATUS,Z		
        goto L_ACK                ; Comparator = 1 => Light led
        goto L_NOTH               ; Comparator = 0 => loop     
L_ACK        
        MOVLW       11100000B       
        MOVWF       PORTB        
        goto L_CHECK 
L_NOTH
        MOVLW       00000000B   
        MOVWF       PORTB        
        goto L_CHECK        
        

DELAY	movlw	d'250'			;delay 250 ms (4 MHz clock) to make run faster or slower change the d'250' setting
	movwf	count1
d1	movlw	0xC7
	movwf	counta
	movlw	0x01
	movwf	countb
Delay_0
	decfsz	counta, f
	goto	$+2
	decfsz	countb, f
	goto	Delay_0

	decfsz	count1	,f
	goto	d1
	return
	
    END

 

[Papabravo]

anyone with analog input or comparator.

What do those peripherals have to do with running a Java or Python interpreter? Not much I'll venture a guess. It is the amount of program memory and the amount of data memory that are key indicators of the feasibility of realizing your goal. They are different on a Harvard arhitecture like the PIC16 family.

A quick check on source forge reveals that Python is written in C++ and Python. So I guess the first hurdle is to get a legitimate C++ compiler for the PIC family of interest. So here is me throwing down the gauntlet. If you can find a python interpreter that runs on any member of the PIC family I will be one surprised puppy.

 

[jumpjack]

Most of PIC programs are just a matter of turning on a pin depending on the status of another pin.
Once my SW will be ready (HW is already there: a PIC connected to GND and Vcc is all we need!), we'll be able to do this just by properly programming in python/java/flashlite/whatelse-runs-on-a-phone

Is out there any ready-made source to identify the frequency of an analog signal with a PIC?

 

[kchriste]

Tone detection using a PIC which could be useful to you:
**broken link removed**
If you really want to use Java and HTML on a PIC (Well served up by a PIC and running on something else like a web enabled phone) then look into an ethernet interface:
**broken link removed**
and you can control the PIC from anywhere in the world where internet access is available.

 

[jumpjack]

Tone detection using a PIC which could be useful to you:
**broken link removed**
If you really want to use Java and HTML on a PIC (Well served up by a PIC and running on something else like a web enabled phone) then look into an ethernet interface:
**broken link removed**
and you can control the PIC from anywhere in the world where internet access is available.

thanks for links, but they are too complex, I'm looking for something very simple.
I just found out that all I need in mi phone2pic circuit is ONE component: the PIC!
I connected phone audio output directly to 16f628a comparator, and it was able to detect signal and to light a led when the signal is present.

Determining signal frequency should be just a matter of counting how many times signal goes high in a second.

Any idea about how I can simulate an analog sinusoidal input in MPLAB PIC simulator?