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Does anyone have any experience with this development system using PBP? I am a newbie, and I am trying to use a Pic16F628A to write to the on board LCD screen. It appears to be connected to port B - can't seem to get it to work. Can anyone send a simple sample program that might work?
Thank you for any help.
i have an ep7board it appears to be very similar to a ep6 schematically for the lcd connections. i have experienced no trouble with the lcd. only issue i have using those old style chips is getting the programmer to verify chip. iirc the pgm pin needs to pulled down for success.
you provide no detail and can't get it to work is pretty vague.
what have you tried ? and what happens ?
It appears that the LCD is connected to Port B. I think by default the PIC 16F628A uses Port A. I just do not know how to tell the PIC to use Port B. What PIC are you using with Easypic 7? I was hoping someone could send me the pic basic code that would provide me with a simple test.
my code looks like this:
CMCON = 7
DEFINE LCD_DREG PORTB
DEFINE LED_DBIT 0
DEFINE LCD_RSREG PORTB
DEFINE LCD_RSBIT 4
DEFINE LCD_EREG PORTB
DEFINE LCD_EBIT 5
DEFINE LCD_BITS 4
DEFINE LCD_LINES 2
PAUSE 1000
LCDOUT $FE,1
LCDOUT "HELLO"
PAUSE 1000
END
oops - correcting a typo and an omission - this is the code that I am trying
TRISB=0
CMCON = 7
DEFINE LCD_DREG PORTB
DEFINE LCD_DBIT 0
DEFINE LCD_RSREG PORTB
DEFINE LCD_RSBIT 4
DEFINE LCD_EREG PORTB
DEFINE LCD_EBIT 5
DEFINE LCD_BITS 4
DEFINE LCD_LINES 2
PAUSE 1000
LCDOUT $FE,1
LCDOUT "HELLO"
PAUSE 1000
END
Thank you for any help
i don't see why that will not work , assuming the pic config you have omitted showing is correct
can you blink a led ?
this works fine for a 648a , a 628a's rich brother
Code:'****************************************************************'* Name : LCD_TEST.BAS *
'* Author : RICHARD *
'* Date : 4/8/2017 *
'* Version : 1.0 *
'* Notes : pic16f648a ep7 *
'* : 2016 LCD *
'****************************************************************
#CONFIG
__config _INTOSC_OSC_NOCLKOUT & _WDT_ON & _PWRTE_OFF & _MCLRE_ON & _BODEN_ON & _LVP_OFF & _DATA_CP_OFF & _CP_OFF
#ENDCONFIG
DEFINE OSC 4
'LCD defines begin here
DEFINE LCD_BITS 4 'defines the number of data interface lines (4 or 8)
DEFINE LCD_DREG PORTB 'defines the port where data lines are connected to
DEFINE LCD_DBIT 0 'defines the position of data lines for 4-bit interface (0 or 4)
DEFINE LCD_RSREG PORTB 'defines the port where RS line is connected to
DEFINE LCD_RSBIT 4 'defines the pin where RS line is connected to
DEFINE LCD_EREG PORTB 'defines the port where E line is connected to
DEFINE LCD_EBIT 5 'defines the pin where E line is connected
DEFINE LCD_COMMANDUS 1500 'defines the delay after LCDOUT statement
DEFINE LCD_DATAUS 50 'delay in micro seconds
'END of LCD DEFINES
Pause 500 ' LCD initialize time
lcdout $FE,1
LCDOUT $fe,$83,"HELLO"
LCDOUT $fe,$c8,"World"
stop
end
ps rb4 must be pulled low if using ep7 on board programmer or else pgm load will never verify
Yes I can flash an LED - no issues with programming or compiling this code - just does not work for me.
Quote:
Yes I can flash an LED - no issues with programming or compiling this code - just does not work for me.
starting a new tread with the same problem , not even with any extra info probably will get you no further.
yes pbp defaults to porta for lcd thats why the defines are used , the defines overwrite the defaults
what are your config fuse settings ?
what version of pbp are you using ?
did you try my code ?
i assume you ep6 is connected like this
Attachment 8828
Sorry abt the second thread - just getting frustrated!
I did try your code but did not work - I know your code must be solid so maybe it is a fuse setting or a hardware issue?
I am using PBP 3.0.8.0 compiler with the mikroProg suite as my software. It lets you set the config bits when you load the hex file. My config bits set the oscillator as internal, watchdog timer enabled, power up disabled, master clear enabled, brown out detect enabled, low voltage program disabled, Data EE disabled. I can flash an LED so I know the PIC is good and everything is working on that end.
Thanks so much for taking the time and energy to help - I will try again tomorrow.
My connections are just like you printed
Could the fuse settings be an issue? What software do you use to program your Easypic7? I could not get microcode studio to work with it - it does not seem to be able to find the board.
it often is that or failure to set pins to digital, its not the code thats a problem. i assume the contrast is not an issue and that the lcd works and the ep6 board is undamaged and has no conflicting jumper/switch settingsQuote:
Could the fuse settings be an issue?
Attachment 8829Quote:
What software do you use to program your Easypic7?
I could not get microcode studio to work with it - it does not seem to be able to find the board.
command line use for the mikro onboard icd doesn't seem to be a possibility, its not going to run from the msc button.
i just load the hex file manually , if you compile my code the config fuse settings are embedded in the hex file
there is no need to set them
you could upgrade to 3.0.10 for free
you realise there are two 18pin skts on the board for different chip pinouts, you need to use the proper one
i set my pins to digital using cmcon=7 , but I think that only sets Port A to digital. By default, is port B digital? Do I need a command to do that?
I will try your code again tonight - thank you so much for your help!
I do realize there are two sockets - i am using socket B, and I can flash an LED so I think it is set up correctly
the code I posted sets up everything necessary to use the lcd. only porta has analogue attributes and plays no part in this exerciseQuote:
i set my pins to digital using cmcon=7 , but I think that only sets Port A to digital. By default, is port B digital? Do I need a command to do that?
cmcon=7 will disable the comparator module and set porta pins to digital mode on that chip
but can you set each and every portb pin needed for lcd to flash a led and do they flash at the set rate,Quote:
I do realise there are two sockets - i am using socket B, and I can flash an LED so I think it is set up correctly
the problem is not the lcd code
just a thought , you're not trying to use the built in cog serial lcd are you ?
Attachment 8841
Not using the serial LCD
ok then its back to simple fault finding
1. can you verify portb pins 0 to 5 actually work
2. do pins b0 to b5 get to the lcd socket
3. are pins b0 to b5 shorted to something not intended
4. does the lcd have power,gnd and contrast connections that work
5. does the lcd even work
Hi stargazer
I think you have the defines for the LCD wrong. Have a look at the schematic in the user manual for the LCD. You will see that portb.0 to portb.3 is connected to the HIGH four data bits of the LCD.
Change
DEFINE LCD_DBIT 0
to
DEFINE LCD_DBIT 4
Check that the LCD has power (I think you have to set a switch or jumper). Your LCD should burst into life.
Phil
I am delighted to report success! Well, sort of. Richard - you started me thinking about a possible hardware issue so I started snooping around with my meter. On the LCD pins, I was seeing some very strange readings - pins shorted together, etc. I upgraded to an Easypic 7 and used your code, and it works like a charm. Not sure why my easy pic 6 was damaged - I barely used it - been sitting in a drawer. BTW with the easy pic 7 that was a great tip about pulling RB4 low - chip will not program unless it is held low ( not sure why?)
Thanks so much for taking the time to help me!
not quite the solution i expected , still you're up and running