RC5 decode on a 10F + Question

Hi all,

I needed to build a philips RC5 IR decoder, in order to be able to control some other circuitry. When a predefined key is received an decoded the corresponding IO is made high.

However, the example source code's if found could not fit a 10F202.

I used a TSOP(TK)1836 connected to GPIO.0, and in order to "see" the values received the pic sends it's data trough a max232 to my pc. This is only for debug purposes, and must be removed later (removing the moddefs include and serout will free up lots ofprogram memory).

Code:

---

'==== Set fuses ================================================================
@ device pic10F202,wdt_off,mclr_off,protect_off

'==== Set includes =============================================================
INCLUDE "modedefs.bas"                          ' Include for Serout

'==== Set XTAL =================================================================
DEFINE OSC 4                                    ' int XTAL @ 4 Mhz

'==== Set variables ============================================================
Y VAR word                                      ' To Hold the 12-bit RC5 code


'==== Set IO ===================================================================   
IR_PIN VAR GPIO.0                              ' GPIO.0 input pin reading IR data
SERIAL var GPIO.1                              ' GPIO.1 SEROUT 9600-8-n-1 output
TRISIO = %00001001                              ' Set TRIS register input's & output's
OPTION_REG.7 = 0                                ' Internal pull-ups = on

'==== Signal information =======================================================
'Given the information found on http://www.sbprojects.com/knowledge/ir/rc5.htm
'The incoming RC5 signal will look like this :
'
'bit      1    2    3    4    5    6    7    8    9  10  11  12  13  14
'      |    |    |    |    |    |    |    |    |    |    |    |    |    |    |
'uSec  1778 1778 1778 1778 1778 1778 1778 1778 1778 1778 1778 1778 1778 1778

'==== Main program ============================================================= 
MAIN:
IF IR_PIN = 1 THEN GOTO MAIN                    ' Wait for the first bit to arive
y.13 = IR_PIN                                    ' Incoming signal
pauseus 889                                    ' In order to se this 0 we are in the second
                                                ' period of the first 1.778 msec, so we will
                                                ' wait another 889 usec to enter the 2nd period.

pauseus 1600                                    ' Almost at the end of the second period, look for
y.12 = IR_pin                                    ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.11 = IR_pin                                    ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.10 = IR_pin                                    ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.9 = IR_pin                                    ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.8 = IR_pin                                    ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.7 = IR_pin                                    ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.6 = IR_pin                                    ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.5 = IR_pin                                    ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.4 = IR_pin                                    ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.3 = IR_pin                                  ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.2 = IR_pin                                  ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.1 = IR_pin                                  ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.0 = IR_pin                                  ' a high or low signal
pauseus 178                                    ' Time to the end of this period

y = ~y                                          ' Invert y word
if Y.lowbyte = 255 then goto ERROR              ' If all lowbytes are 0xFF then noise is received

'==== DEBUG , output received data serial ======================================
Serout serial,T9600,["STX= ",#y.13,#Y.12,#Y.11,10,13]
Serout serial,T9600,["SYS= ",#y.10,#y.9,#y.8,#y.7,#y.6,13,10]               
Serout serial,T9600,["CMD= ",#Y.5,#y.4,#y.3,#y.2,#y.1,#Y.0,13,10]

'==== End of main loop reset and look again ====================================
ERROR:                                       
Y=0                                        ' Clear key codes
PAUSE 250                                  ' debounce
GOTO MAIN                                  ' Return to main loop

---

My problem now is:
The variable Y is a WORD the has bit's 0 to 13 stored with info.
How do i break up the word in to 3 sections ?

bits 0 to 2 '000' are for the S1, S2 and toggle bit
bits 3 to 7 '00000' are for the System address
bits 8 to 13 '000000' are for the command bits

I want to end up with 2 variables SYSTEM(5 bits) and COMMAND(6 bits)

Anyone ?
(Also, comments on my code are very welcome !!!)

Thanks !

Quote:

---

My problem now is:
The variable Y is a WORD the has bit's 0 to 13 stored with info.
How do i break up the word in to 3 sections ?

bits 0 to 2 '000' are for the S1, S2 and toggle bit
bits 3 to 7 '00000' are for the System address
bits 8 to 13 '000000' are for the command bits

I want to end up with 2 variables SYSTEM(5 bits) and COMMAND(6 bits)

---

Simple bit level manipulation as described in the PBP manual...i.e.
temp var byte
temp.bit0 = y.bit0
temp.bit1 = y.bit1
....and so on and so on...

Ahhh, a classic case of RTFM ! You are so right !

I tried it but it seems i cannot declare another byte.

CMD VAR BYTE
ERROR: Unable to fit variable CMD

Even with the modedefs include removed .....

Is there a way to free up some program memory ?

The 10F202 has 24 bytes of data memory, so why can't i fit 1 word and 1 byte ?


Thanks !

Yes, get rid of the MODEDEFS...
Other tips that might help out...
Use DEBUG instead of SEROUT
Instead of inline code, grab the bits in a loop.
Not sure if it'll save anything, you've got pauseus and pause. Maybe just use a big pauseus rather than both commands.
Treat your Y variable as a word initially, then when you changing it up, treat it as 2 bytes, y.high and y.low. Might have to declare a couple of smaller bit variables (maybe scavenge a bit from a register from a module you're not using, like maybe a timer that's not running) while doing the bit swapping.
This might be one of those 'codius minimus' projects...DT? Anyone else?

Hi Skimask,

Thanks for your fast reply, will try the things you indicated.

I also found that commenting out the RR1, RM1 and flag section in pbpPIC12.ram gives
an extra 3 bytes !

Thanks !

I don't think I'd ever try PBP with a 10F ... just not enough room to spare.
Much better to use ASM.

Here's one from Bruce.

PIC10F200 Automated IR Light Switch
http://www.picbasic.co.uk/forum/showthread.php?t=3261

Doesn't do what you want, but it shows what you can do with a 10F200 and ASM.
<br>

ultiblade,

I just compiled your code for a 10F202 with PBP 2.50, and it all fit's. No Errors.
I did not change the .RAM file.

Which version of PBP do you have?
<br>

Quote:

---

Originally Posted by Darrel Taylor

I don't think I'd ever try PBP with a 10F ... just not enough room to spare.
Much better to use ASM.

Here's one from Bruce.

PIC10F200 Automated IR Light Switch
http://www.picbasic.co.uk/forum/showthread.php?t=3261

Doesn't do what you want, but it shows what you can do with a 10F200 and ASM.
<br>

---

Amazing ! Missed that, i was only searching for 'RC5' examples ...
Maybe coming wintertime will bring me a new hobby, learning Assembly !

I'm using pbp2.47. Yesterday i made some code changes, but it still won't fit without
the ram file change. I commented out only the FLAG parameter, that does the trick.

Here's the code until now, works perfect with a RC5 remote. It now act's like a sort of a IR RC5 to binary encoder. Just press the number buttons 0 to 7 on the remote and the 3 IO outputs will be set accordingly ... (Just one minor thing, still remains : the FLAG section has to be commented out in the pbppic12.ram file, for me to be able to fit TMP as byte)

Code:

---


'==== Set fuses =====================================================
@ device pic10F202,wdt_off,mclr_off,protect_off


'==== Set XTAL =====================================================
DEFINE OSC 4                                    ' int XTAL @ 4 Mhz

'==== Set variables ==================================================
Y VAR word                                      ' To Hold the 12-bit RC5 code
TMP var BYTE

'==== Set IO =======================================================   
IR_PIN VAR GPIO.3                              ' GPIO.0 input pin reading IR data
'SERIAL var GPIO.1                              ' GPIO.1 SEROUT 9600-8-n-1 output
RES1 var GPIO.0                                  ' Binary 1
RES2 var GPIO.1                                  ' Binary 2
RES3 var GPIO.2                                  ' Binary 4

OPTION_REG.7 = 0                                ' Internal pull-ups = on
TRISIO = %00001000                            ' Set TRIS register input's & output's
OPTION_REG.5 = 0                                ' Set Timer inc. on internal inst.
GPIO  = %00000000                              ' Set all digital low

'==== Signal information ===============================================
'Given the information found on http://www.sbprojects.com/knowledge/ir/rc5.htm
'bit      1    2    3    4    5    6    7    8    9  10  11  12  13  14
'      |    |    |    |    |    |    |    |    |    |    |    |    |    |    |
'uSec  1778 1778 1778 1778 1778 1778 1778 1778 1778 1778 1778 1778 1778 1778

'==== Main program ================================================== 
MAIN:
IF IR_PIN = 1 THEN GOTO MAIN                    ' Wait for the first bit to arive
y.13 = IR_PIN                                    ' Incoming signal
pauseus 889                                    ' In order to se this 0 we are in the second
                                                ' period of the first 1.778 msec, so we will
                                                ' wait another 889 usec to enter the 2nd period.

pauseus 1600                                    ' Almost at the end of the second period, look for
y.12 = IR_pin                                    ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.11 = IR_pin                                    ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.10 = IR_pin                                    ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.9 = IR_pin                                    ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.8 = IR_pin                                    ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.7 = IR_pin                                    ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.6 = IR_pin                                    ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.5 = IR_pin                                    ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.4 = IR_pin                                    ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.3 = IR_pin                                  ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.2 = IR_pin                                  ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.1 = IR_pin                                  ' a high or low signal
pauseus 178                                    ' Time to the end of this period

pauseus 1600                                    ' Almost at the end of this period, look for
y.0 = IR_pin                                  ' a high or low signal
pauseus 178                                    ' Time to the end of this period

y = ~y                                          ' Invert y word

if Y.lowbyte = 255 then goto ERROR              ' If all lowbytes are 0xFF then noise is received


'==== Parse received values  =========================================
TMP.1 = Y.13
TMP.0 = Y.12
if not tmp = 3 then goto error

TMP.4 = Y.10
TMP.3 = Y.9
TMP.2 = Y.8
TMP.1 = Y.7
TMP.0 = Y.6
if not tmp = 0 then goto error

TMP.2 = Y.5
TMP.1 = Y.4
TMP.0 = Y.3
if tmp > 0 then goto error

TMP.2 = Y.2
TMP.1 = Y.1
TMP.0 = Y.0

OPTION_REG.5 = 0                                ' Internal pull-ups = on
res3 = tmp.2
res2 = tmp.1
res1 = tmp.0           

'==== End of main loop reset and go from top ============================
ERROR:                                       
Y=0
tmp=0                                      ' Clear key codes
PAUSE 250                                  ' debounce
GOTO MAIN                                  ' Return to main loop

END

---

And again: THANK YOU guys !

Best Regards, UltiBlade