Guru
Joined: 11/02/2018
Location: AustraliaPosts: 3407
| Posted: 08:16am 23 Sep 2024 |
To go with the NEC protocol here is Philips RC-5
Sub IR_RC5_Rx and Sub IR_RC5_Tx are the useful bits in this program.
The rest just reads and decodes the Manchester protocol, sending the result to the console.
Then transmits the IR code 3 seconds later to the device so you can verify that it is correct. The codes it produces match the published ones so it should be ok.
The older version of RC-5 sends a Start pulse, a Control bit to distinguish a double press from auto-repeat, a 5 bit device code and a 6 bit key code.
As that only gives 64 key codes the current version has a Field bit between the Start and Control bits to provide another 64 key codes.
Field = 1 for keys 0 to 63
Field = 0 for keys 64 to 127
Control alternates between 0 and 1 on each key press.
Sub IR_RC5_Tx should work with all the above but the devices I have (Philips audio system & Schaub Lorenz TV) both use Start = 1 & Field = 1 so the others are untested.
For old devices that don't use the Field bit set the Start bit to 0 and the Field bit to 1. The Field bit becomes the Start bit.
Usage: IR_RC5_Tx start, field, control, device, key
Eg: IR_RC5_Tx 1,0,17,63 turns on the sterio and IR_RC5_Tx 1,1,17,12 turns it off.
If you want to modify the subs for your own projects there are plenty of comments and diagnostic prints to help.
' "IR Philips RC-5 code Rx & Tx.bas"
'Option explicit
Dim integer RxPin=MM.Info(pinno GP1), TxPin=MM.Info(pinno GP0) ' set GPxx for IR Tx & Tx
Dim Integer N = 29 ' expected maximum number of transitions, plus a few
Dim integer m, b(N), c(N\2), dev, key, r(N*2), strt=1, Tend
Dim Float T
SetPin RxPin, intl, IR_RC5_Rx 'wait for IR activity to pull IRpin low
SetPin TxPin, DOUT : Dim integer ctrl '<-- only needed for Sub IR_RC5_Tx demo
Print " To send commands un-comment 2 lines in the loop at the end of the program then:-"
Print " Start = 1 for new RC-5, Start = 0 for original (obsolete) RC-5"
Print " Field = 1 for Key codes 0 to 63, Field = 0 for Key codes 64 to 127"
Print " Control toggle between 0 and 1 on each Key press to distinguish from auto-repeat"
Print " Device = device code, 0 to 31"
Print " Key = Key code, 0 to 63. Field = 0 shifts these up by 128" : Print
Print " Press a key on the IR remote control to record the RC-5 code" : Print
Sub IR_RC5_Rx
T=Timer :Tend = T
SetPin RxPin, off : SetPin RxPin, Din :m=1 :b(0)=0
Do While m<(N-1)And(Timer-T<300) 'get pulses/pauses & convert to Manchester bits
Do While (Pin(RxPin)=0(And(Timer-T<300) :Loop
If (Timer-T)>2.2 Then Exit Do
b(m)=1:If (Timer-T)>1.6 Then:Inc m :b(m)=1:EndIf
T=Timer :Inc m
Do While (Pin(RxPin)=1)And(Timer-T<300):Loop
If (Timer-T)>2.2 Then Exit Do
b(m)=0:If (Timer-T)>1.6 Then:Inc m :b(m)=0:EndIf
T=Timer :Inc m
Loop
SetPin RxPin, off : b(N)=Timer-Tend : m=0 'disable interrupt while processing
' Print :Print "IR BitStream - b() ";:Math V_Print b()
If b(4)+b(5)+b(6)+b(7)+b(8)=0 Then GoTo no.data
If b(N-2)=0 And b(N-3)=0 Then strt = 0 'detect obsolete RC-5 code (no field bit)
If b(N-2)=1 Xor b(N-3)=1 Then strt = 1 'detect new RC-5 code (with field bit)
If strt = 0 Then
For m=(N-2) To 0 Step -1
b(m+2)=b(m)
Next
b(0)=0 : b(1)=0
EndIf
m=2
Do While m<(N) 'convert pairs of Manchester half-bits to ordinary bits
If (b(m)=0)And(b(m+1)=1) Then c(m\2-1)=1
If (b(m)=1)And(b(m+1)=0) Then c(m\2-1)=0
Inc m, 2
Loop
Print "c()=bits ";:Math V_print c()
field=c(0): ctrl=c(1): dev=0: key=0
'ctrl toggles on each key press to distinguish autorepeat from double press
For m=2 To 6:Inc dev,dev +c(m):Next 'assemble Device code
For m=7 To 12:Inc key,key +c(m):Next 'assemble Key code
If strt=1 Then Print "field";field;" control";ctrl;" dev";dev;" key";key
If strt=0 Then Print "old RC-5 no field. control";ctrl;" dev";dev;" key";key
' Pause 3000 : IR_RC5_Tx 1, field, ctrl, dev, key 'resend the received code after 3S
' ctrl=Not ctrl
no.data:
T=0
Math set 0, b()
Math set 0, c()
Pause 400 'block repeat codes
SetPin RxPin, intl, IR_RC5_Rx 're-enable interrupt for next key
End Sub
Sub IR_RC5_Tx(strt, field, ctrl, dev, key) As integer
strt=strt And 1 : field=field And 1 : ctrl=ctrl And 1 : dev=dev And 31 : key=key And 63
Local integer ord(14), bs(900), m=0, n, z
Math set 14, bs() 'load BitStream array with 36kHz half cycles (14uS)
'assemble ordinary bit array
For n=6 To 2 Step -1 : ord(n) = (dev >> m) And 1 : Inc m :Next
m=0
For n=12 To 7 Step -1 : ord(n) = (key >> m) And 1 : Inc m :Next
If strt = 0 Then field = 1
ord(0)=field : ord(1)=ctrl
' Print "f";field,"c";ctrl,"dev";dev,"key";key,, "ord()";:Math V_print ord()' :Print
' Print " b() ";:Math V_Print b()' :Print
'convert ordinary bits to pairs of Manchester half-bits and load into BitStream array -
'merging adjacent high or low pairs of half-bits into long highs or long lows,
' without causing inversions in the BitStream
'half cycle at 36kHz = 14uS = 64 or 65 half cycles per short pulse, 129 per long pulse
m=0
If strt=1 Then m=64 'Else m=1 'm=65 -> start pulse
If (field=1)And(strt=1) Then : bs(65)=889 :Inc m,65 : EndIf
If (field=0)And(strt=1) Then : Inc m,64 : bs(m)=889 : EndIf
If strt = 0 Then m=65
For n=0 To 11
If (ord(n)=1)And(ord(n+1)=1) Then : bs(m)=889 : Inc m,64 : EndIf
If (ord(n)=1)And(ord(n+1)=0) Then : Inc m,64 : bs(m)=889 : EndIf
If (ord(n)=0)And(ord(n+1)=1) Then : bs(m)=1778 : Inc m,64 : EndIf
If (ord(n)=0)And(ord(n+1)=0) Then : bs(m)=889 : Inc m,64 : EndIf
Next
Inc m
' BitBang BitStream TxPin, m, bs() 'for ARMMiteF4
Device BitStream TxPin, 832+66*strt, bs() 'for PicoMite
Pause 88
Device BitStream TxPin, 832+66*strt, bs() 'for PicoMite
Pin(TxPin) = 0 'ensure correct polarity for next run
' Print : Math V_print bs() :Print
End Sub
Do 'un-comment the next 2 lines to send data
'Input "Enter RC-5 Data:- Start, Field, Control, Device, Key ";strt,field,ctrl,dev,key
'IR_RC5_Tx strt,field,ctrl,dev,key
Pause 400
Loop
End
'Option explicit
Dim integer RxPin=MM.Info(pinno GP1), TxPin=MM.Info(pinno GP0) ' set GPxx for IR Tx & Tx
Dim Integer N = 29 ' expected maximum number of transitions, plus a few
Dim integer m, b(N), c(N\2), dev, key, r(N*2), strt=1, Tend
Dim Float T
SetPin RxPin, intl, IR_RC5_Rx 'wait for IR activity to pull IRpin low
SetPin TxPin, DOUT : Dim integer ctrl '<-- only needed for Sub IR_RC5_Tx demo
Print " To send commands un-comment 2 lines in the loop at the end of the program then:-"
Print " Start = 1 for new RC-5, Start = 0 for original (obsolete) RC-5"
Print " Field = 1 for Key codes 0 to 63, Field = 0 for Key codes 64 to 127"
Print " Control toggle between 0 and 1 on each Key press to distinguish from auto-repeat"
Print " Device = device code, 0 to 31"
Print " Key = Key code, 0 to 63. Field = 0 shifts these up by 128" : Print
Print " Press a key on the IR remote control to record the RC-5 code" : Print
Sub IR_RC5_Rx
T=Timer :Tend = T
SetPin RxPin, off : SetPin RxPin, Din :m=1 :b(0)=0
Do While m<(N-1)And(Timer-T<300) 'get pulses/pauses & convert to Manchester bits
Do While (Pin(RxPin)=0(And(Timer-T<300) :Loop
If (Timer-T)>2.2 Then Exit Do
b(m)=1:If (Timer-T)>1.6 Then:Inc m :b(m)=1:EndIf
T=Timer :Inc m
Do While (Pin(RxPin)=1)And(Timer-T<300):Loop
If (Timer-T)>2.2 Then Exit Do
b(m)=0:If (Timer-T)>1.6 Then:Inc m :b(m)=0:EndIf
T=Timer :Inc m
Loop
SetPin RxPin, off : b(N)=Timer-Tend : m=0 'disable interrupt while processing
' Print :Print "IR BitStream - b() ";:Math V_Print b()
If b(4)+b(5)+b(6)+b(7)+b(8)=0 Then GoTo no.data
If b(N-2)=0 And b(N-3)=0 Then strt = 0 'detect obsolete RC-5 code (no field bit)
If b(N-2)=1 Xor b(N-3)=1 Then strt = 1 'detect new RC-5 code (with field bit)
If strt = 0 Then
For m=(N-2) To 0 Step -1
b(m+2)=b(m)
Next
b(0)=0 : b(1)=0
EndIf
m=2
Do While m<(N) 'convert pairs of Manchester half-bits to ordinary bits
If (b(m)=0)And(b(m+1)=1) Then c(m\2-1)=1
If (b(m)=1)And(b(m+1)=0) Then c(m\2-1)=0
Inc m, 2
Loop
Print "c()=bits ";:Math V_print c()
field=c(0): ctrl=c(1): dev=0: key=0
'ctrl toggles on each key press to distinguish autorepeat from double press
For m=2 To 6:Inc dev,dev +c(m):Next 'assemble Device code
For m=7 To 12:Inc key,key +c(m):Next 'assemble Key code
If strt=1 Then Print "field";field;" control";ctrl;" dev";dev;" key";key
If strt=0 Then Print "old RC-5 no field. control";ctrl;" dev";dev;" key";key
' Pause 3000 : IR_RC5_Tx 1, field, ctrl, dev, key 'resend the received code after 3S
' ctrl=Not ctrl
no.data:
T=0
Math set 0, b()
Math set 0, c()
Pause 400 'block repeat codes
SetPin RxPin, intl, IR_RC5_Rx 're-enable interrupt for next key
End Sub
Sub IR_RC5_Tx(strt, field, ctrl, dev, key) As integer
strt=strt And 1 : field=field And 1 : ctrl=ctrl And 1 : dev=dev And 31 : key=key And 63
Local integer ord(14), bs(900), m=0, n, z
Math set 14, bs() 'load BitStream array with 36kHz half cycles (14uS)
'assemble ordinary bit array
For n=6 To 2 Step -1 : ord(n) = (dev >> m) And 1 : Inc m :Next
m=0
For n=12 To 7 Step -1 : ord(n) = (key >> m) And 1 : Inc m :Next
If strt = 0 Then field = 1
ord(0)=field : ord(1)=ctrl
' Print "f";field,"c";ctrl,"dev";dev,"key";key,, "ord()";:Math V_print ord()' :Print
' Print " b() ";:Math V_Print b()' :Print
'convert ordinary bits to pairs of Manchester half-bits and load into BitStream array -
'merging adjacent high or low pairs of half-bits into long highs or long lows,
' without causing inversions in the BitStream
'half cycle at 36kHz = 14uS = 64 or 65 half cycles per short pulse, 129 per long pulse
m=0
If strt=1 Then m=64 'Else m=1 'm=65 -> start pulse
If (field=1)And(strt=1) Then : bs(65)=889 :Inc m,65 : EndIf
If (field=0)And(strt=1) Then : Inc m,64 : bs(m)=889 : EndIf
If strt = 0 Then m=65
For n=0 To 11
If (ord(n)=1)And(ord(n+1)=1) Then : bs(m)=889 : Inc m,64 : EndIf
If (ord(n)=1)And(ord(n+1)=0) Then : Inc m,64 : bs(m)=889 : EndIf
If (ord(n)=0)And(ord(n+1)=1) Then : bs(m)=1778 : Inc m,64 : EndIf
If (ord(n)=0)And(ord(n+1)=0) Then : bs(m)=889 : Inc m,64 : EndIf
Next
Inc m
' BitBang BitStream TxPin, m, bs() 'for ARMMiteF4
Device BitStream TxPin, 832+66*strt, bs() 'for PicoMite
Pause 88
Device BitStream TxPin, 832+66*strt, bs() 'for PicoMite
Pin(TxPin) = 0 'ensure correct polarity for next run
' Print : Math V_print bs() :Print
End Sub
Do 'un-comment the next 2 lines to send data
'Input "Enter RC-5 Data:- Start, Field, Control, Device, Key ";strt,field,ctrl,dev,key
'IR_RC5_Tx strt,field,ctrl,dev,key
Pause 400
Loop
End
Getting the BitStream to work properly with Manchester half-bits realy taxed my geriatric brain. Senility is advancing.
Edit 29/09/2024
The code above has been edited. A closer inspection of the output for the old version of RC-5 was not quite right. Should now be ok, but still can't test on an actual device.
However sending from one Pico to another does work and scope pics of the data appear to match the specification.
Also added automatic detection of old RC-5 to IR_RC5_Rx Sub.
Output when receiving.
RUN
Press a key on the IR remote control to record the RC-5 code
field 1 control 0 dev 1 key 53
field 1 control 1 dev 1 key 0
field 1 control 0 dev 17 key 63
field 1 control 1 dev 17 key 7
field 1 control 0 dev 18 key 63
old RC-5 no field. control 1 dev 28 key 0
field 0 control 0 dev 20 key 63
field 0 control 1 dev 20 key 8
field 0 control 0 dev 20 key 54
field 1 control 1 dev 20 key 63
Press a key on the IR remote control to record the RC-5 code
field 1 control 0 dev 1 key 53
field 1 control 1 dev 1 key 0
field 1 control 0 dev 17 key 63
field 1 control 1 dev 17 key 7
field 1 control 0 dev 18 key 63
old RC-5 no field. control 1 dev 28 key 0
field 0 control 0 dev 20 key 63
field 0 control 1 dev 20 key 8
field 0 control 0 dev 20 key 54
field 1 control 1 dev 20 key 63
Edited 2024-09-29 14:31 by phil99