Prop-1 / LCD/ Solenoid

[gadget-evilusions]

Hello,

I am asking for help, as I don't fully understand outputting to an LCD display yet.

I have a Parallax 2 x 16 back lit serial LCD, 27977. A Prop-1, an normally open switch, and a 10k potentiometer.

1. I would like a program to read the potentiometer, and convert that input to a range of 0-500ms.
2. Display that 0-500ms value on the LCD screen in semi-real time.
3. When the normally open switch is pressed, I want to turn on a 12vdc solenoid, hooked up to Out1, for a time equal to the 0-500ms range from the potentiometer.
4. Reset.

It's the monitoring of the pot and displaying it on the LCD that is befuddling me.

[JonnyMac]

Sorry for the delay. Here's a simple version to get things started. Once things are working we can tweak the value. Remember that the Prop-1 has an in-line resistor on the IO pins so the pot will never go down to zero; once you know what the low-end value is we can adjust that out.

Notice that the debounce loop is actually using the time to read the pot and update the display as its timing pad.

' =========================================================================
'
'   File...... solenoid_timer.bs1
'   Purpose...
'   Author.... JonnyMac
'   E-mail....
'   Started...
'   Updated...
'
'   {$STAMP BS1}
'   {$PBASIC 1.0}
'
' =========================================================================


' -----[ Program Description ]---------------------------------------------


' -----[ Revision History ]------------------------------------------------


' -----[ I/O Definitions ]-------------------------------------------------

SYMBOL  Adjust          = 7                     ' no ULN, SETUP = REMOVED
SYMBOL  TX              = 6                     ' no ULN, SETUP = DN
SYMBOL  Trigger         = PIN5                  ' N.O. between P5.R & P5.W

SYMBOL  Solenoid        = PIN1                  ' V+ and OUT1


' -----[ Constants ]-------------------------------------------------------

SYMBOL  YES             = 1
SYMBOL  NO              = 0

SYMBOL  IS_ON           = 1
SYMBOL  IS_OFF          = 0


' LCD

SYMBOL  LCD_BKSPC       = $08                   ' move cursor left
SYMBOL  LCD_RT          = $09                   ' move cursor right
SYMBOL  LCD_LF          = $0A                   ' move cursor down 1 line
SYMBOL  LCD_CLS         = $0C                   ' clear LCD (use PAUSE 5 after)
SYMBOL  LCD_CR          = $0D                   ' move pos 0 of next line
SYMBOL  LCD_BLON        = $11                   ' turn backlight on
SYMBOL  LCD_BLOFF       = $12                   ' turn backlight off
SYMBOL  LCD_OFF         = $15                   ' LCD off
SYMBOL  LCD_ON1         = $16                   ' LCD on; cursor off, blink off
SYMBOL  LCD_ON2         = $17                   ' LCD on; cursor off, blink on
SYMBOL  LCD_ON3         = $18                   ' LCD on; cursor on, blink off
SYMBOL  LCD_ON4         = $19                   ' LCD on; cursor on, blink on
SYMBOL  LCD_LINE1       = $80                   ' move to line 1, column 0
SYMBOL  LCD_LINE2       = $94                   ' move to line 2, column 0

SYMBOL  LCD_CC0         = $F8                   ' define custom char 0
SYMBOL  LCD_CC1         = $F9                   ' define custom char 1
SYMBOL  LCD_CC2         = $FA                   ' define custom char 2
SYMBOL  LCD_CC3         = $FB                   ' define custom char 3
SYMBOL  LCD_CC4         = $FC                   ' define custom char 4
SYMBOL  LCD_CC5         = $FD                   ' define custom char 5
SYMBOL  LCD_CC6         = $FE                   ' define custom char 6
SYMBOL  LCD_CC7         = $FF                   ' define custom char 7


' -----[ Variables ]-------------------------------------------------------

SYMBOL  debounce        = B2                    ' for trigger debouncing
SYMBOL  digit           = B3

SYMBOL  solTiming       = W5


' -----[ Initialization ]--------------------------------------------------

Power_Up:
  HIGH TX                                       ' set LCD serial to idle
  PAUSE 250                                     ' let LCD initialize
  SEROUT TX, T2400, (LCD_BLON, LCD_ON1, LCD_CLS)

Reset:
  PINS = %01000000                              ' set LCD serial to idle
  DIRS = %01000010                              ' set P6 and P1 to output

  debounce = 0


' -----[ Program Code ]----------------------------------------------------

Main:
  POT Adjust, 100, solTiming                    ' *** Use Run->Pot Scaling

  solTiming = solTiming * 2 MAX 500             ' scale and limit

  ' update LCD

  SEROUT TX, T2400, (LCD_LINE1)                 ' cursor home

  digit = solTiming / 100 + "0"                 ' extract 100s
  SEROUT TX, T2400, (digit)

  solTiming = solTiming // 100
  digit = soltiming / 10 + "0"                  ' extract 10s
  SEROUT TX, T2400, (digit)

  solTiming = solTiming // 10 + "0"             ' extract 1s
  SEROUT TX, T2400, (digit)


Check_Trigger:
  debounce = debounce + 1 * Trigger             ' count display loops
  IF debounce < 10 THEN Main


Run_Solenoid:
  Solenoid = IS_ON
  PAUSE solTiming
  Solenoid = IS_OFF
  GOTO Reset


' -----[ Subroutines ]-----------------------------------------------------


' -------------------------------------------------------------------------


' -------------------------------------------------------------------------


' -------------------------------------------------------------------------


' -----[ User Data ]-------------------------------------------------------