LCDout Command causes Interrupt!!??

Can LCDout break interrupts for some reason?

My project runs fine with an interrupt on RB0 leading to a menu system. In the menu system, it displays a menu choice and then waits to see if RB1 is brought HIGH indicating a selection. If selected, it returns to the main program loop. This is working fine.

THEN, I went to add an LCD using LCDout, the interrupt gets somehow tripped without pressing the button, and the RB1 button does nothing!! Adding just one "LCDout $FE, XXX" command does this. Remove it, and it goes back to normal!!! (It does the same thing wth the LCD physically connected or not)

Can anyone think why adding the "LCDout" stuff would mess up my interrupt routine, and eliminate the operation of B1 on a totally different port than the LCD is even on?

Here is the environment:

PIC 18F2525
8 Mhz internal Osc
External EEPROM
Serial data in, processed, and displayed or stored on EEPROM

LCD is on RA.0-RA.3, RA.4,RA.5.

Interrupt line is on RB.0, second button is on RB.1

I2C is on RC3,RC4

Seral data I/O is on RB4,RB5, and RC

Program setup includes:
' -----[ Fuses ]------------------------------------------------
@ __CONFIG _CONFIG1H, _OSC_INTIO67_1H
@ __CONFIG _CONFIG2H, _WDT_ON_2H & _WDTPS_128_2H
@ __CONFIG _CONFIG3H, _PBADEN_OFF_3H & _MCLRE_OFF_3H
@ __CONFIG _CONFIG4L, _LVP_OFF_4L & 0bfh ;_XINST_OFF_4L
'
' -----[ Includes/Defines ]---------------------------------------------------------
include "modedefs.bas" 'include serout defines
'Define loader_used 1 Used for bootloader only

OSCCON=%01111000
DEFINE OSC 8
While OSCCON.2=0:Wend

DEFINE LCD_DREG PORTA ' Set data pin of LCD to
DEFINE LCD_DBIT 0 ' PORTA.0-PORTA.3

DEFINE LCD_RSREG PORTA ' Set RS bit of LCD to
DEFINE LCD_RSBIT 4 ' PORTA.5

DEFINE LCD_EREG PORTA ' Set E bit of LCD to
DEFINE LCD_EBIT 5 ' PORTA.4

DEFINE LCD_LINES 4 ' 4 Lines LCD
DEFINE LCD_COMMANDUS 2000 'Define delay time between sending LCD commands
DEFINE LCD_DATAUS 50 'Define delay time between data sent.

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

ADCON0 = %00110000 ' turn off - select port AN12 (nothing)
ADCON1 = %00001111 ' turn portA to digital I/O (same as dec 15)

CMCON = $07 ' turn off
HLVDCON = %00000000 ' turn off
CVRCON = $00000000 ' turn off

SSPCON1 = %11011100 ' supposed to be turning on I2C
SSPCON2 = %01111000 ' supposed to be turning on I2C

INTCON = %11110000 ' TG guess at 2525 interrups for all INT pins
INTCON2= %01110100 ' rising edge of INT0,1,2 RB0,1,2
RCON = %10000000 ' no priority interrups

T1CON = %11000000 'Timer1 1:1 prescale??

Init:
PORTA = %00000000 'Initialize PortA to all zeros - all output
TRISA = %00000000 'All port A output
PORTB = %00010001 'Initialize PortB - port 5 for data, port 0 for button interrupt
TRISB = %00010001 'Port 2 inputs are 0 and 5
PORTC = %00010000 '
TRISC = %00010000 ' SCL I2C clock out



On Interrupt Goto INT_handle

Bmenu = 1
Smenu = 0

ReStart:
TMR1H = 0 ' Clear time counts before Timer1 re-start
TMR1L = 0 ' Clear time counts before Timer1 re-start
PIR1.0 = 0 ' CLear over-flow flag before enable
T1CON.0 = 1 ' Turn Timer1 back on before entry into MainProcedure

Main:' ****** [Main Program Loop] *
PROGRAM LOOP
Goto Main


' Interrupt handler at end of program
NextStage: ' timer routine
Mnu = 0
T1CON.0 = 0 ' Turn off Timer1
Timer = 0 ' Clear Timer var on entry here
TMR1H = 0
TMR1L = 0 ' CLear timer count registers as required
serout2 ALCDout, LCDbd, [I,CLR]
serout2 ALCDout, LCDbd,[I,L1_C1]
serout2 ALCDout, LCDbd, ["Timer Ran Out"]
pause 1000
GOTO ReStart ' When you're ready to start all over

' Interrupt handler stuff here

Disable ' Disable interrupts in handler
INT_handle:
Timer = 0 ' Clear Timer var on entry here
TMR1H = 0
TMR1L = 0 ' CLear timer count registers as required
Selectit=0
While selectit = 0
Mnu=1 ' we are in the menu system
If Mmenu = 0 then
While Mmenu = 0 ' waiting until
wend ' push-button is release
pause 100 ' debounce time
Bmenu=Bmenu+1
endif ' bo pressed – go to next menu

Select Case Bmenu
Case 1
serout2 ALCDout, LCDbd, [I,CLR]
serout2 ALCDout, LCDbd,[I,L1_C1]
serout2 ALCDout, LCDbd, ["Sensors & Sats"]
pause 10
Case 2
serout2 ALCDout, LCDbd, [I,CLR]
serout2 ALCDout, LCDbd,[I,L1_C1]
serout2 ALCDout, LCDbd, ["Lat/Long"]
pause 10
Case 3
serout2 ALCDout, LCDbd, [I,CLR]
serout2 ALCDout, LCDbd,[I,L1_C1]
serout2 ALCDout, LCDbd, ["Speed/Volts"]
pause 10
Case 4
serout2 ALCDout, LCDbd, [I,CLR]
serout2 ALCDout, LCDbd,[I,L1_C1]
serout2 ALCDout, LCDbd, ["Altitude"]
pause 10

Bmenu=1
end select
If PortB.1 = 1 then ' select button is pressed
While MMenu = 0 ' waiting until
wend ' push-button is release
pause 100 ' debounce time
selectit = 1 ' b1 pressed get out of the loop!
endif
Wend

Mnu=0 ' turn off menu flag

Here:
While MMenu = 0 ' waiting until
wend ' push-button is release
pause 100 ' debounce time
If MMenu = 0 then here
PIR1.0 = 0 ' Clear Timer1 over-flow flag
Timer = 0 ' Clear Timer counts before return
INTCON.1=0 ' reset RB0 interrupt flag
Resume ' Return to main program

Enable ' Enable interrupts after
' handler

end

One things spring to mind now. your LCD is connected to SS(slave Select) pin. and your peripheral interrupts are enable. Try to disable peripheral interrupt first. If it's working, try to disable the MSSP interrupts with PIE1.3=1

I guess it could be this... i didn't read the whole datasheet but... worth a try

I have tried a few things - thanks for the reply. What seems to have worked is turning off Timer0 all together..

T0CON = 1

.... Seems to keep the LCD from triggering the interrupt / timer whichever it was!!

NOW THAT IT WORKS, I have another issue seems to be that the LDCout command is not displaying the first character --

LCDout $fe, 1
LCDout $FE, $C0
LCDout $FE, "P:",#Dec_mb dig 4,#Dec_mb dig 3, #Dec_mb dig 2,#Dec_mb dig 1, ".",dec1 Dec_mb,"F:",#Dec_tempf dig 3, #Dec_tempf dig 2,#Dec_tempf dig 1, ".",dec1 Dec_Tempf

Displays "1013.3F:73.2"

It is SUPPOSED to display "P:1013.3F:73.2"

Why does the "P:" disappear?? I tried putting in " P:", and it still is not there!!

Why does LCDout not like "P:"??

Thanks!

Tom

Quote:

---

Originally Posted by Tom Gonser

<br>
LCDout $FE, "P:",#Dec_mb dig 4,#Dec_mb dig 3, #Dec_mb dig 2,#Dec_mb dig 1, ".",dec1 Dec_mb,"F:",#Dec_tempf dig 3, #Dec_tempf dig 2,#Dec_tempf dig 1, ".",dec1 Dec_Tempf

Displays "1013.3F:73.2"

It is SUPPOSED to display "P:1013.3F:73.2"

---

Tom,

The $FE at the biginning of the LCDOUT makes PBP think the next character is a Command. But instead it's the "P" that you want to display. If you remove the $FE it should work better.

Darrel

That at least is an easy answer...

You have LCDOUT $FE...

either put a control character after the $FE (eg $FE,$C0 to position on the 2nd line), of lose the $FE.

so either...

LCDout $FE,$C0,"P:",#Dec_mb dig 4,#Dec_mb dig 3, #Dec_mb dig 2,#Dec_mb dig 1, ".",dec1 Dec_mb,"F:",#Dec_tempf dig 3, #Dec_tempf dig 2,#Dec_tempf dig 1, ".",dec1 Dec_Tempf

or

LCDout "P:",#Dec_mb dig 4,#Dec_mb dig 3, #Dec_mb dig 2,#Dec_mb dig 1, ".",dec1 Dec_mb,"F:",#Dec_tempf dig 3, #Dec_tempf dig 2,#Dec_tempf dig 1, ".",dec1 Dec_Tempf

Bah! Beaten to an answer!

THANKS!! That does help. I have another question tho on LCD positioning:

If I just say

LDCout $fe, 1
LCDout $fe, 2
LCDout " Hi There"

It shows up as

"re" on the first line of the display... I have to add a bunch of

LCDout $fe, $10, $10, $10, $10, $10

to get it to move over... Why is this think thinking the edge of the screen is so far OFF the screen to the left??

Tom

what about if you use only
LCDOUT $FE,1,"Hi there!!!"


add a pause 2000 at the begining of your code?

And now remove those DEFINE LCD_COMMANDUS and DEFINE LCD_DATAUS???

Had the delay between commands at 500.. Switched to 2000 and it seems to have fixed it.. Where is it waiting for TWO SECONDS to do anything??

It appear that some LCD brand need big start-up delay. try decreasing it to PAUSE 1000.