FullDuplex Issues

Comments

• Mike G Posts: 2,702

  2010-04-03 00:47 edited 2010-04-03 00:47

  If your trying to write to an LCD display than use one the of the LCD objects. Writing to a PC Monitor? Use one the the VGA objects. The TV_Terminal outputs to a TV terminal.
  
  Right tool for the job.
  
  Post Edited (Mike G) : 4/3/2010 12:52:03 AM GMT
• Mike G Posts: 2,702

  2010-04-03 00:57 edited 2010-04-03 00:57

  Also it's probably a good idea to start the your objects in the start method. When you post code please use the code tags. It makes reading the code in the forum easier.
  
  You might want to read the Propeller manual.
  
  

  CON
  _clkmode = xtal1 + pll16x
  _xinfreq = 5_000_000
  NewLine = 13
  ClearScreen = 0
  rxpin = 30
  txpin = 31
  mode = 2
  baudrate = 9600
  
  
  OBJ
  VideoDisplay: "TV_Terminal"
  XB : "FullDuplexSerial"
  '
  PUB Start
  '
    DisplayTextOnMonitor
  '
  PRI DisplayTextOnMonitor | data
  
    VideoDisplay.start(12) 'Initializes the VideoDisplay object
    SetScreenWhiteOnDarkBlue 'Calls a procedure that sets the foreground
    ' color to white and the background color
  
    XB.start(rxpin, txpin, mode, baudrate)
    data := XB.rx
  
  
    VideoDisplay.out(data)
  
  
  
  
  PRI SetScreenWhiteOnDarkBlue 'Sets the foreground color to white and the
    VideoDisplay.out(3) ' background color to dark blue on the monitor.
    VideoDisplay.out(5)
  
• kkumar5 Posts: 2

  2010-04-03 01:26 edited 2010-04-03 01:26

  I feel like a moron after having fixed my problem
  
  i had a floating ground issue which was not letting the propeller decode the data right....it took me 5 hours to find it so i paid for my mistake in full
  
  thansk for the help guys
• Alarus Posts: 48

  2013-01-16 23:49 edited 2013-01-16 23:49

  Why, the 11 bits instead of 10 bits?
  Is not it reduces the Baudrate of transmission?

  transmit                jmpret  txcode,rxcode         'run a chunk of receive code, then return
  
                          mov     t1,par                'check for head <> tail
                          add     t1,#2 << 2
                          rdlong  t2,t1
                          add     t1,#1 << 2
                          rdlong  t3,t1
                          cmp     t2,t3           wz
          if_z            jmp     #transmit
  
                          add     t3,txbuff             'get byte and inc tail
                          rdbyte  txdata,t3
                          sub     t3,txbuff
                          add     t3,#1
                          and     t3,#$0F
                          wrlong  t3,t1
  
                          or      txdata,#$100          'ready byte to transmit
                          shl     txdata,#2
                          or      txdata,#1
                          mov     txbits,#11
                          mov     txcnt,cnt
  
  :bit                    test    rxtxmode,#0  wz    'output bit on tx pin according to mode
                          test    rxtxmode,#0  wc
          if_z_and_c      xor     txdata,#1
                          shr     txdata,#1       wc
          if_z            muxc    outa,txmask        
          if_nz           muxnc   dira,txmask
                          add     txcnt,bitticks        'ready next cnt
  
  :wait                   jmpret  txcode,rxcode         'run a chunk of receive code, then return
  
                          mov     t1,txcnt              'check if bit transmit period done
                          sub     t1,cnt
                          cmps    t1,#0           wc
          if_nc           jmp     #:wait
  
                          djnz    txbits,#:bit          'another bit to transmit?
  
                          jmp     #transmit             'byte done, transmit next byte
  

  
  Should be replaced by:
  

                          or      txdata,#$100          'ready byte to transmit
                          shl     txdata,#2
                          or      txdata,#1
                          mov     txbits,#11
                          mov     txcnt,cnt
  
  

  
  by:
  

                          or      txdata,#$100          'ready byte to transmit
                          shl     txdata,#1
                          mov     txbits,#10
                          mov     txcnt,cnt
  
• SRLM Posts: 5,045

  2013-01-17 03:08 edited 2013-01-17 03:08

  It's probably 1 start, 8 data, and 2 stop. The double stop bit is to help the receiver get back on track if it's off by a bit.
• Alarus Posts: 48

  2013-01-17 03:11 edited 2013-01-17 03:11

  Should have different modes (8N1 8E1 8O1 8N2 etc.).
• SRLM Posts: 5,045

  2013-01-17 10:39 edited 2013-01-17 10:39

  Alarus wrote: »

  Should have different modes (8N1 8E1 8O1 8N2 etc.).

  
  Why? In four years of using FDS, I've never come across the need for anything but the default. Can you provide examples of common devices whose only communication is asynchronous serial that is uncommon?
  
  ps: And you're always free to modify to suit. That's the nice thing about the Propeller hardware: it's all software. You get to choose.
• Alarus Posts: 48

  2013-01-17 17:21 edited 2013-01-17 17:21

  Such as Modbus, requires 8E1 mode. Older terminals require 7N1 mode as they work with ASCII.