PIC16F88 senior design

[mackrackit]

Did you set the OSC type in PBP *.inc file for this chip.

And if you did what did you set it for.

Or you can do it on this line that I do not see in the new code.

@ DEVICE MCLR_OFF, PROTECT_OFF, WDT_OFF,_XT_OSC

Double check the data sheet on this, I do not have it in front of me.

[mister_e]

The guy use a 20MHz, so, should be something like HS_OSC instead of XT_OSC.

Anyways open the M16F88.inc file and enjoy the config fuse list

					; *** DEVICE Fuses Definitions
EXTRC_OSC_CLKOUT equ    3FEC0013h       ; XX XXXX XXX1 XX11
EXTRC_OSC_NOCLKOUT equ  3FEC0012h       ; XX XXXX XXX1 XX10
EXTRC_OSC       equ     3FEC0012h       ; XX XXXX XXX1 XX10
INTRC_OSC_CLKOUT equ    3FEC0011h       ; XX XXXX XXX1 XX01
INTRC_OSC_NOCLKOUT equ  3FEC0010h       ; XX XXXX XXX1 XX00
INTRC_OSC       equ     3FEC0010h       ; XX XXXX XXX1 XX00
EXTCLK_OSC      equ     3FEC0003h       ; XX XXXX XXX0 XX11
EC_OSC          equ     3FEC0003h       ; XX XXXX XXX0 XX11
HS_OSC          equ     3FEC0002h       ; XX XXXX XXX0 XX10
XT_OSC          equ     3FEC0001h       ; XX XXXX XXX0 XX01
LP_OSC          equ     3FEC0000h       ; XX XXXX XXX0 XX00
WDT_ON          equ     3FFB0004h       ; XX XXXX XXXX X1XX
WDT_OFF         equ     3FFB0000h       ; XX XXXX XXXX X0XX
PWRT_ON         equ     3FF70000h       ; XX XXXX XXXX 0XXX
PWRT_OFF        equ     3FF70008h       ; XX XXXX XXXX 1XXX
MCLR_ON         equ     3FDF0020h       ; XX XXXX XX1X XXXX
MCLR_OFF        equ     3FDF0000h       ; XX XXXX XX0X XXXX
BOD_ON          equ     3FBF0040h       ; XX XXXX X1XX XXXX
BOD_OFF         equ     3FBF0000h       ; XX XXXX X0XX XXXX
LVP_ON          equ     3F7F0080h       ; XX XXXX 1XXX XXXX
LVP_OFF         equ     3F7F0000h       ; XX XXXX 0XXX XXXX
CPD_ON          equ     3EFF0000h       ; XX XXX0 XXXX XXXX
CPD_OFF         equ     3EFF0100h       ; XX XXX1 XXXX XXXX
WRT_1FOURTH     equ     39FF0000h       ; XX X00X XXXX XXXX
WRT_HALF        equ     39FF0200h       ; XX X01X XXXX XXXX
WRT_3FOURTHS    equ     39FF0400h       ; XX X10X XXXX XXXX
WRT_OFF         equ     39FF0600h       ; XX X11X XXXX XXXX
DEBUG_ON        equ     37FF0000h       ; XX 0XXX XXXX XXXX
DEBUG_OFF       equ     37FF0800h       ; XX 1XXX XXXX XXXX
CCPMX_ON        equ     2FFF0000h       ; X0 XXXX XXXX XXXX
CCPMX_OFF       equ     2FFF1000h       ; X1 XXXX XXXX XXXX
PROTECT_ON      equ     1FFF0000h       ; 0X XXXX XXXX XXXX
PROTECT_OFF     equ     1FFF2000h       ; 1X XXXX XXXX XXXX

					; *** DEVICE2 Fuses Definitions
FCMEN_OFF	equ     3FFE0000h       ; XX XXXX XXXX XXX0
FCMEN_ON	equ     3FFE0001h       ; XX XXXX XXXX XXX1
IESO_OFF	equ     3FFD0000h       ; XX XXXX XXXX XX0X
IESO_ON		equ     3FFD0002h       ; XX XXXX XXXX XX1X

interesting this DEVICE2 option... for those using PM

[mackrackit]

The guy use a 20MHz, so, should be something like HS_OSC instead of XT_OSC.

My mistake

[rhino]

I know when I was in school, they always made us flow chart out the process first. Would you be able to do something like that for us, because honestly, I'm a little confused by your program.
some examples...

INCLUDE "modedefs.bas"
DEFINE OSC 20
INPUTDATA var byte
X VAR BYTE
X = 0
MAIN:
PORTB.5 = 0
SEROUT PORTB.1,T9600,[1]
WAITLOOP:
SERIN PORTA.1,T9600,[inputdata]
if inputdata <> "A" then goto waitloop
LOOP:
IF (X<4) THEN
HIGH PORTB.5
PAUSE 2
LOW PORTB.2
PAUSE 2
X = X+1
GOTO LOOP
endif
goto MAIN

SERIN PORTA.1,T9600,[inputdata]

'What is the value of inputdata the first time this runs?  If you are using "A" for a qualifier, the statement should be
SERIN PORTA.1,T9600,["A"],inputdata
'This statement will wait for until "A" comes in, then puts data after that into variable inputdata

IF (X<4) THEN

'I usually write
IF X<4 THEN

Did you ever get your hands on a PBP manual?

[AlaskanEE]

I'm trying to get the backlight of my LCD to light when a voltage high is recieved on a pin from a push button circuit. I'm testing to see if I can send A to the LCD screen then have it pause then send a B every time I input a voltage high. The loop works and it sends serial data then pauses then sends serial data then goes back to outputing low voltage till a high is recieved again. The problem is that the LCD just is showing solid squares instead of the leters that I am trying to send. I've looked up the ASCII binary, decimal, and hexadecimal equivolents for A and B and sent the numbers with %, nothing, and $ preceeding the numbers equivolently all with the same result. Here's my code.

@ DEVICE MCLR_OFF, PROTECT_OFF, WDT_OFF
INCLUDE "modedefs.bas"
DEFINE OSC 20
DEFINE LCD_LINES 2
ANSEL = %00000000
TRISB.1 = 0
TRISB.0 = 1
WAITLOOP:
LOW PORTB.1
if PORTB.0 = 0 then goto waitloop
IF PORTB.0 = 1 THEN
serout PORTB.1,T9600,[65]
pauseus 14000
serout PORTB.1,T9600,[66]
ENDIF
goto WAITLOOP

this is the code with the decimal notation being used. I don't understand should I just try sending A i.e. serout portb.0,t9600,[A] or is that wrong as well?

[skimask]

DEFINE LCD_LINES 2

If you are using a parallel mode LCD (Hitachi 44780 based), then PBP requires quite a few more defines to get it to work (see the manual).
If you are using a serial mode LCD (usually a parallel LCD mounted on a PCB with another PIC doing the decoding duties), then the DEFINE shown above isn't going to do anything for you. And you'll want to refer to the manual for the LCD.
And it would most likely help a lot if we knew what kind of LCD you were using...
Get the manual! And read it! We can help you with a lot of stuff...but again...I, for one, am not into hand-holding.

[rhino]

OK... now we're on a different subject.

What type of LCD are you using? If it is a serial LCD, you don't need the following line.

DEFINE LCD_LINES 2

If it is not a serial display and it has an HD44780 controller, you need some other LCD defines in there. But since I don't know, I'm going to assume it's a serial display. Next the serial part. Try...

serout PORTB.1,T9600,["A"]

Next, the blocks on the LCD... try adjusting the contrast.

edit: Looks like Skimask was quicker on the draw. Ignore redundant information from me.

[AlaskanEE]

I'm sorry, earlier I copied down my old code that was rittled with errors and didn't have the input and outputs set. Here is the new code:

INCLUDE "modedefs.bas"
DEFINE OSC 20
ANSEL = %00000000
INPUTDATA var byte
TRISA.2 = 1
TRISB.2 = 0
PORTA.2 = INPUTDATA
X VAR BYTE
X = 0
MAIN:
PORTB.2 = 0
WAITLOOP:
SERIN PORTA.2,T9600,[inputdata]
if inputdata <> "A" then goto waitloop
LOOP:
IF X<4 THEN
HIGH PORTB.2
PAUSE 2
LOW PORTB.2
PAUSE 2
X = X+1
GOTO LOOP
endif
goto MAIN

I want pin A.2 to be the input from the bluesmirf, which will be sending messages to our LCD via serial ports. The serial data will come into the pic through porta.2. Each message that is sent by the bluesmirf will be proceeded by the letter A. I'd like porta.2 to not accept any random data and only activate the loop when a message is recieved that is preceeded by the letter A. The output should be a high then low loop that loops four times. The output should come from portb.2

[skimask]

I don't understand should I just try sending A i.e. serout portb.0,t9600,[A] or is that wrong as well?

Yes, that is also wrong...
serout portb.0 , t9600 , [ "A" ]
which is also in the manual...
Your original line:
serout portb.0 , t9600 , [ A ]
will output the value equivalent to the variable A.

[skimask]

edit: Looks like Skimask was quicker on the draw. Ignore redundant information from me.

And I was just about to say to ignore redundant information from ME!

[AlaskanEE]

The LCD we're using is the serial enabled LCD SerLCD v2.5 it's default settings are 9600 bps with eight bits of data, 1 start bit, 1 stop bit, and no parity. I wasn't sure of the DEFINE LCD_LINES 2 command, but I figured it couldn't hurt since our LCD is 2 lines, and since the LCD is a serial input I didn't think I needed any of the LCDIN/LCDOUT commands.

[AlaskanEE]

yeah I forgot the quotes on A. It all made sense in my mind, if you could just stop being selfish and start reading other peoples minds this would be much easier

[skimask]

The LCD we're using is the serial enabled LCD SerLCD v2.5 it's default settings are 9600 bps with eight bits of data, 1 start bit, 1 stop bit, and no parity. I wasn't sure of the DEFINE LCD_LINES 2 command, but I figured it couldn't hurt since our LCD is 2 lines, and since the LCD is a serial input I didn't think I needed any of the LCDIN/LCDOUT commands.

Ok, that's better.
You've got serout xxxx , t9600 , xxxxx
Try n9600 instead of t9600 and see what happens. Refer to your LCDs spec's to see which one you actually need.

[rhino]

Ok, give this a try...

INCLUDE "modedefs.bas"
DEFINE OSC 20
ANSEL = %00000000
INPUTDATA var byte 
TRISA.2 = 1
TRISB.2 = 0
'''''''PORTA.2 = INPUTDATA 'don't need this line
X VAR BYTE 
X = 0
MAIN:
PORTB.2 = 0
WAITLOOP:
SERIN PORTA.2,T9600,["A"],inputdata
'''''''''''if inputdata <> "A" then goto waitloop ' don't need this line
LOOP: 
IF X<4 THEN 
HIGH PORTB.2 
PAUSE 2         'Question here... do you really want to pause for 2 milliseconds?
LOW PORTB.2
PAUSE 2         'same question here
X = X+1
GOTO LOOP
endif
goto MAIN

[AlaskanEE]

I made an earlier post asking about that. I'm using an external oscilator set up with a 20MHz oscillator and with the input and out puts going through 47uF capacitors to ground and their perspective input and output oscilator pins on the PIC. When I used PAUSE 500 for a half second pause, it paused for a lot longer than half a second. I lowered it down to 2 and it paused for about a second so I just went with it and just posted a question about it on here

[mackrackit]

See post 41 and 42

[rhino]

I made an earlier post asking about that. I'm using an external oscilator set up with a 20MHz oscillator and with the input and out puts going through 47uF capacitors to ground and their perspective input and output oscilator pins on the PIC. When I used PAUSE 500 for a half second pause, it paused for a lot longer than half a second. I lowered it down to 2 and it paused for about a second so I just went with it and just posted a question about it on here

I usually use 20pF caps. If you're having that much trouble with the PAUSE statement, I can't for the life of me figure out how the serial timing will ever work. Have you tried 15 (recommended in the datasheet) or 20 pF caps on the oscillator?

[AlaskanEE]

I switched to using the internal oscillator set to 4MHz to see if I could get the pause timing down and it worked. I also switched the serout baud rate setting from t9600 to n9600, but alas I'm still getting random output on the LCD. I'm trying to just get an "A" to appear on the LCD then a 10 second pause then have a "B" appear. This is the code I have:

@ DEVICE PIC16F88,INTRC_OSC_NOCLKOUT
@ DEVICE PIC16F88,PROTECT_OFF
@ DEVICE PIC16F88,WDT_OFF
@ DEVICE PIC16F88,PWRT_ON
@ DEVICE PIC16F88,MCLR_ON
@ DEVICE PIC16F88,BOD_OFF
@ DEVICE PIC16F88,LVP_OFF
@ DEVICE PIC16F88,CPD_OFF
@ DEVICE PIC16F88,DEBUG_OFF
@ DEVICE PIC16F88,CCPMX_OFF
OSCCON = %01100000 '4MHz
INCLUDE "modedefs.bas"
ANSEL = %00000000
TRISB.1 = 0
TRISB.0 = 1
WAITLOOP:
LOW PORTB.1
if PORTB.0 = 0 then goto waitloop
IF PORTB.0 = 1 THEN
serout PORTB.1,N9600,[$41]
pause 10000
serout PORTB.1,N9600,[$42]
ENDIF
goto WAITLOOP
end

the LCD seems to output random charichters but the ones that showed up most offten and in this order where: (). Should I try a different baud rate in my code?

[Pic_User]

Hi AlaskanEE,

If you are going to become an Analog Electrical Engineer this year, you got to get used to the terminology.

There are “clock oscillators”. These are little circuits that have 4 leads. They need 5 Volts and common supply (input) and have a signal and common output. Generally they are rectangle shaped and have similar pin spacing to a standard IC package with pins only near the corners. The signal output is an acceptable square-wave. These can be used with PIC Microchip. Not very often. These would not use capacitors on the PIC connection.
And
There are “crystals”. Crystals are used to help an external (external to the crystal) circuit maintain a “rock solid” frequency. Crystals are used internal to the “clock oscillators”. Crystals are passive devices and generally have two leads. A crystal cannot oscillate without additional components. Some type of active circuit, with positive feedback is usually used. The PIC has all the components needed for oscillating with a crystal. Except, the xxpf capacitors to common, on each crystal lead.

In light of the above this is difficult to understand:

I'm using an external oscilator set up with a 20MHz oscillator and with the input and out puts going through 47uF capacitors to ground and their perspective input and output oscilator pins on the PIC.

[skimask]

Start small and work your way up!
I don't know how much programming you've done, if you've made a blinky LED, follow a switch, etc.etc.
The program below should (according to the datasheet) reset the LCD back to defaults (forget about that switch, the backlight, the serial communications, etc.) and just output the alphabet, one character every 1/4 second and repeat itself over and over again...

@ DEVICE PIC16F88,INTRC_OSC_NOCLKOUT
@ DEVICE PIC16F88,PROTECT_OFF
@ DEVICE PIC16F88,WDT_OFF
@ DEVICE PIC16F88,PWRT_ON
@ DEVICE PIC16F88,MCLR_ON
@ DEVICE PIC16F88,BOD_OFF
@ DEVICE PIC16F88,LVP_OFF
@ DEVICE PIC16F88,CPD_OFF
@ DEVICE PIC16F88,DEBUG_OFF
@ DEVICE PIC16F88,CCPMX_OFF
OSCCON = %01100000 '4MHz
INCLUDE "modedefs.bas"
ANSEL = %00000000
TRISB.1 = 0
TRISB.0 = 1
dataout var byte

Waitloop:
serout portb.1 , n9600 , [ $32 ] 'according to serlcdv2.5 datasheet, should reset LCD back to 9600 (defaults) if it's stuck on some other baud rate

for dataout = 64 to 89
serout portb.1 , n9600 , [ dataout ]
pause 250
next dataout

goto waitloop
end


Also, according to the datasheet, are you even seeing the 'splashscreen' during power up? If not, you've got other problems. Read the datasheet, you'll see it.

EDIT:
I forgot to mention...
The 4mhz internal oscillator isn't exactly accurate. If you're getting random characters, that might be the reason.
9600 baud is at the upper end of SEROUT's usability at 4mhz. In this case, it should be ok, but if your 4mhz internal oscillator is a bit low, it might end up being TOO low.

[AlaskanEE]

I've fixed the external oscilator problem, changing out the caps with lower valued ones worked. Now to work on getting the LCD to time corectly output the data. Just to make sure 20MHz should be able to handle a 9600 baude rate without any trouble shouldn't it? Also is there and extra code I need to add to ensure stable operation outside of '@ DEVICE PIC16F88, HS_OSC' and DEFINE 20?

[skimask]

I've fixed the external oscilator problem, changing out the caps with lower valued ones worked. Now to work on getting the LCD to time corectly output the data. Just to make sure 20MHz should be able to handle a 9600 baude rate without any trouble shouldn't it? Also is there and extra code I need to add to ensure stable operation outside of '@ DEVICE PIC16F88, HS_OSC' and DEFINE 20?

20mhz is plenty high to use with 9600 baud (Appendix A of the PBP manual).
DEFINE 20 is not the correct usage for that DEFINE (Section 4.16)

[AlaskanEE]

I know I forgot to put OSC between DEFINE and 20. Anyways here's the code I used trying to get an alphabet output to go through using the 20 MHz external oscillator. the LCD showed a new character every .25 seconds but they were all random characters. Seems like a timing issue to me.

[AlaskanEE]

ohh I also tried the original code that skimask used working with the internal oscilator, it gave the same result, successive random symbols and leters.

[skimask]

ohh I also tried the original code that skimask used working with the internal oscilator, it gave the same result, successive random symbols and leters.

Again, generally, random symbols and characters usually mean the baud rate is just a tad too far off. And I know you're not this far, but 'generally speaking' (not a hard fact, but usually accuracte), if the baud rate is a bit slow, you get framing errors, too fast gives overrun errors.

[AlaskanEE]

is it possible for me to use a baude rate other than 2400bps or 9600bps?

[skimask]

is it possible for me to use a baude rate other than 2400bps or 9600bps?

Here's a program for you:

MAIN:
LCDOUT "See the manual as noted in earlier posts."
Goto Main

[rhino]

See the manual as noted in earlier posts.

Yep.... I think it's time to stop.... take a deep breath.... do a flowchart of what you want this project to do. Draw out a schematic, write your code, then post it all here. There seems to be a lot of jumping around to different problems. We're sixty some posts along now, and I'm not sure if you're making any progress.

[rhino]

AlaskanEE -
Are you still out there?

[skimask]

AlaskanEE -
Are you still out there?

Maybe he found the manual and, more importantly, read it. And now he's learned so much good stuff, that he doesn't need our help nearly as much anymore.

[Pic_User]

Maybe he found the manual and, more importantly, read it. And now he's learned so much good stuff, that he doesn't need our help nearly as much anymore.

And of course we will now see him, back here helping others!
-Adam-

[skimask]

And of course we will now see him, back here helping others!
-Adam-

Exactly what I was thinking.
Does it work any other way?