Weired results with Serial_Lcd

marzec309 · 2009-04-16 04:16

OK, I'm stumped. I just got my First propeller today and I'm slowly grasping the propeller language. But when I try to link to a Parallax 4x20 serial lcd, using the Serial_LCD Object from the Object Exchange, I get weird results. Text doesn't show up as expected. Well here's the simple test code I'm try to use.

CON
  _CLKMODE = XTAL1 + PLL16X
  _XINFREQ = 5_000_000

OBJ
  LCD           : "Serial_Lcd"

PUB main
  WAITCNT(clkfreq / 10 + cnt)
  LCD.init(9,9600,4)
  LCD.cursor(1)
  LCD.cls
  LCD.backLight(true)
  LCD.str(str1)
  waitcnt(clkfreq * 5 + cnt)

DAT
        str1 byte "Proto Prop Rocks",13,0

The display seems to respond to function commands. But, the text never shows up in the right place. Its shifted off the left egde when it actualy shows up and isn't Smile.

StefanL38 · 2009-04-16 05:15

Hello Marzec,

you have to call the command LCD.str like this

  LCD.str(@str1)

the "@" in this use is called the adress-operator

If you get strange results from something it's always worth a look into the definition of the code

the method str in the file serial_Lcd.spin

PUB str(strAddr)

'' Transmit z-string at strAddr

  serial.str(strAddr)

"strAdr means string ADRESS (=location in memory where the string is stored)

to narrow down problems like this

try variations like this

PUB main
  WAITCNT(clkfreq / 10 + cnt)
  LCD.init(9,9600,4)
  LCD.cursor(1)
  LCD.cls
  LCD.backLight(true)
  LCD.putc("T")
  LCD.putc("e")
  LCD.putc("s")
  LCD.putc("t")
  waitcnt(clkfreq * 5 + cnt)

or

PUB main
  WAITCNT(clkfreq / 10 + cnt)
  LCD.init(9,9600,4)
  LCD.cursor(1)
  LCD.cls
  LCD.backLight(true)
  LCD.str(string("Hello World"))
  waitcnt(clkfreq * 5 + cnt)

best regards

Stefan

marzec309 · 2009-04-19 01:45

Thanks, sometimes I amaze myself. I looked up the definition a few times, just never caught the @ designator.

Weired results with Serial_Lcd

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