Who sees my stupid mistake?

[RuudNL]

Hello,

After not having used picbasic for a couple of years, I decided to create some code to produce MIDI information.
The intended use is to have five buttons to control a DAW.
The code compiles without a problem, but I don't get any MIDI (31.250 Baud) output. Xtal = 20 MHz, PIC = 16F628.
I think I made an obvious mistake, but I don't see what it could be...

'* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
'* MIDI Remote for Reaper            20 MHz resonator (HS)          
'* PIC16F628                         Watchdog timer OFF              
'* PORTA.0 = Output                                                  
'* PORTB.0 = Rewind                                                  
'* PORTB.1 = FastFwd.                                               
'* PORTB.2 = Stop                                                   
'* PORTB.3 = Play                                                   
'* PORTB.4 = Record                                                 
'* PORTB.5 = Switch between: Stop / Stop + Save
'* Version 1.0                                      
'* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * 

TRISB= %00111111                                 ' PORTB.6/7=Output 0..5=Input
CMCON =  7                                             ' Digitale mode
DEFINE OSC 20                                        ' 20 MHZ OSC.

Progstart: 

  if PORTB.0 = 1 then 
    Serout2 PORTB.7, 16384+12, [144, 44, 127]    ' Rewind
  endif  
  if PORTB.1 = 1 then 
    Serout2 PORTB.7, 16384+12, [144, 46, 127]    ' Fast Fwd.
  endif  
  if PORTB.2 = 1 then 
    if PORTB.5 = 0 then                          ' Normal STOP mode
      Serout2 PORTB.7, 16384+12, [144, 48, 127]  ' Stop
    else
      Serout2 PORTB.7, 16384+12, [144, 54, 127]  ' Stop + Save
    endif    
  endif  
  if PORTB.3 = 1 then 
    Serout2 PORTB.7, 16384+3313, [144, 50, 127]  ' Play  
  endif  
  if PORTB.4 = 1 then 
    Serout2 PORTB.7, 16384+3313, [144, 52, 127]  ' Record
  endif  

Debounce:
  Pause 20                                          ' ? shorter ?
  If (PORTB.0=1) or (PORTB.1=1) or (PORTB.2=1) or (PORTB.3=1) or (PORTB.4=1) then
    goto Debounce                                ' Button still pressed?
  endif  
  Goto Progstart

[RuudNL]

I forgot to mention that there are resistors to ground (to keep the input 'low' when no button is pressed) and that the buttons switch to the +5 Volts.

[HenrikOlsson]

16384+12 seems correct for (inverted) 31250 but should it BE inverted and why 16384+3313? (I don't know MIDI...)

Can you do a standard baudrate like 9600 and verify that data is coming out by using a terminal program?

The 16F628 does have UART so HSEROUT will work with it. I'd try that but you might need to invert the signal externally.

[RuudNL]

The 16384+12 is correct, I have used that before.
The calculation is: (1.000.000/Baudrate) - 20 , so 1.000.000 / 31250 = 32 -20 = 12.
For inverted output set bit 14, = 16384.
But even with a different baudrate I don't get any output.

I did a quick test to trace the problem.
With this code, nothing 'toggles':

Progstart: 
  if PORTB.0 = 1 then 
    Toggle PORTB.6
  endif  

Debounce:
  Pause 20                                       ' ? shorter ?
  If PORTB.0=1 then
    goto Debounce                                ' Button still pressed?
  endif  
  Goto Progstart

So I suspect the problem is in the line (and similar lines)

  If PORTB.0=1 then

Although I don't see what could be wrong with this...

[Demon]

If I don't touch programming for a while, I start with blinking a LED to make sure I have the basics working right (config, circuit, programming, etc).

[Demon]

...
If PORTB.0=1
...

You're assuming it can read port B properly.

I'd start even easier, just blink a LED, nothing else, then build from that.

[RuudNL]

So nobody can spot a mistake in my sample code?
Strange, because this line is handled correctly:

If (PORTB.0=1) or (PORTB.1=1) or (PORTB.2=1) or (PORTB.3=1) or (PORTB.4=1) then
.....