Ok then what is the most professional way in most of the cases to configure the pins?Originally Posted by Dave
Should we make all the non used pins as an outputs - low stage?
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Re: GPS Project: PIC18F26K22 or PIC18F46K22
Ok then what is the most professional way in most of the cases to configure the pins?
Should we make all the non used pins as an outputs - low stage?
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Re: GPS Project: PIC18F26K22 or PIC18F46K22
its my understanding that pins left as inputs and tied or pulled down to vss will minimise current consumption.
when i'm breadboarding a design I let them float and have never had an issue , if you accidently plug something
into a input pin at least smoke is not released.
Warning I'm not a teacher
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Re: GPS Project: PIC18F26K22 or PIC18F46K22
Depends. If you care about minimum current as is the case in battery operated devices, then yes. Do set them as inputs with proper pull up enabled inside the PIC or a large size output.
I found that makes no difference, at least for the chips I used, to set them as outputs logic low, and use no pull up or down. Pull up/down can also contribute to current consumption.
I attach the page 2-4 of the Tips and Tricks, file DS01146B regarding I/O that has more info on this.
Ioannis
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Re: GPS Project: PIC18F26K22 or PIC18F46K22
I believe that any input pin must be pulled either up or down depends on the use. If there is a switch normally most of the people, pull up a resistor at the input pin, and the switch goes to ground.
Now for the rest of the pins personally if the pins are output and digital, i leave them floating, but i use the command:
Just read Ioannis previous post. It is really useful info. Thanks a lot.Code:PORTx = low
Last edited by astanapane; - 4th July 2018 at 07:33.
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Re: GPS Project: PIC18F26K22 or PIC18F46K22
Ok lets move forward to the project.
I have received the PIC18F26K22, and connected the ulcd and the Gps module at the EUSARTs.
I tried to configure each EUSART with a different baudrate but didnt work. Anyway i did the baudrate the same for both of the ports and uLCd and GPS worked fine.
Code:'*-----------------------------------------------------------------------------| '* | --------------------- | | '*----------------------- | EUART 1 Configuration | --------------------------| '* | --------------------- | | '*-----------------------------------------------------------------------------| DEFINE HSER_RCSTA 90h ' Enable serial port & continuous receive DEFINE HSER_TXSTA 24h ' Enable transmit, BRGH = 1 DEFINE HSER_CLROERR 1 ' Clear overflow automatically DEFINE HSER_SPBRG 160 ' 38400 Baud @ 64MHz, -0,08% SPBRGH = 1 BAUDCON.3 = 1 ' Enable 16 bit baudrate generator '*-----------------------------------------------------------------------------| '* | --------------------- | | '*----------------------- | EUART 2 Configuration | --------------------------| '* | --------------------- | | '*-----------------------------------------------------------------------------| DEFINE HSER2_RCSTA 90h ' Enable serial port & continuous receive DEFINE HSER2_TXSTA 24h ' Enable transmit, BRGH = 1 DEFINE HSER2_CLROERR 1 ' Clear overflow automatically DEFINE HSER2_SPBRG 160 ' 38400 Baud @ 64MHz, -0,08% SPBRGH2 = 1 BAUDCON2.3 = 1 ' Enable 16 bit baudrate generator '*-----------------------------------------------------------------------------| '*-----------------------------------------------------------------------------|
Then on the main program, i have placed the code to get the information from the GPS and display them to uLcd.
Some coding is still not good, but at the moment i need to solve the problem that is mentioned at the end of this message. So please ignore any minor issues at them moment.
As you see in the main code there is a line that checking if there is no FIX, so will jump to a label notfix:Code:'--------------------------------------------------------------------------------| ' | ' ---------------------------- [ MAIN ] ----------------------------------- | ' | '--------------------------------------------------------------------------------| main: '-------------------------------------------------------------------------------/ ' / ' [ Example NMEA Sentense of GNRMC ] / ' [$GNRMC,090045.000,A,3823.6645,N,02353.3600,E,0.02,195.80,170518,,,A*62] / ' / '--------------------------------------------------------------------------/ ;serin2 gps_tx,84,timeout,lostcable,[wait("$GNRMC"),_ ;we wait for $GNRMC HSERIN timeout,lostcable,[wait("$GPRMC"),_ ;we wait for $GPRMC wait(","),dec2 hh,dec2 mm,dec2 ss,wait("."),dec3 sss,_ ;we wait for 090045.000 which is the time when we got the info wait(","),fix,_ ;we wait for A wait(","),dec2 degrees,dec2 minutes,wait("."),dec4 minutesd,_ ;we wait for 3823.6645 wait(","),dir,_ ;we wait for N/S ;wait(","),dec3 degrees2,dec2 minutes2,wait("."),dec4 minutesd2,_;we wait for 02353.3600 wait(","),dec3 degrees2,dec2 minutes2,wait("."),dec4 minutesd2,_;we wait for 02353.3600 wait(","),dir2,_ ;we wait for E/W wait(","),wait(","),_ wait(","),dec2 day,dec2 month,dec2 year,_ ;we wait for 170518 wait(","),SKIP 3] '------------------------------------------------------------------------------/ ' / ' [ Example NMEA Sentense of GNGGA ] / ' [$GNGGA,140405.000,3823.6010,N,02353.3054,E,1,9,0.88,0.8,M,35.9,M,,*40 / ' / '-------------------------------------------------------------------------/ 'serin2 gps_tx,84,timeout,lostcable,[wait("$GNGGA"),_ ;we wait for GNGGA HSERIN timeout,lostcable,[wait("$GPGGA"),_ ;we wait for GPGGA wait(","),skip 35,_ wait(","),modefix,_ ;we wait for modefix 1,2 or 3 check gps manual for NMEA wait(","),dec2 satno,_ wait(","),skip 19] '------------------------------------------------------------------------------/ ' / ' [ Example NMEA Sentense of GPGSA ] / ' [$GPGSA,A,3,18,08,10,11,14,27,22,32,01,,,,2.62,1.11,2.37*03] / ' / '-------------------------------------------------------------------------/ HSERIN timeout,lostcable,[wait("$GPGSA"),_ wait(","),wait(","),mode2d3d,_ wait(","),SKIP 50] '------------------------------------------------------------------------------/ ' / ' [ Example NMEA Sentense of GPVTG ] / ' [$GPVTG,215.60,T,,M,0.44,N,0.82,K,A*37] / ' / '-------------------------------------------------------------------------/ 'serin2 gps_tx,84,timeout,lostcable,[wait("GNVTG"),_ HSERIN timeout,lostcable,[wait("GPVTG"),wait("N"),_ wait(","),TS[0],TS[1],TS[2],TS[3],TS[4],_ wait(","),SKIP 3] for i = 1 to 3 if TS[i]="." then decimal = i 'TOTAL SPEED. find which character is the decimal point next i select case decimal 'if the gps shows 1.45 it may be 145 'for the conversion ASCII to number we can use the -48 case 1 'decimal position is x.xx SPEED = (10*(TS[0]-48))+(TS[2]-48) case 2 'decimal position is xx.xx SPEED = (100*(TS[0]-48))+(10*(TS[1]-48))+(TS[3]-48) case 3 'decimal position is xxx.xx SPEED = (1000*(TS[0]-48))+(100*(TS[1]-48))+(10*(TS[2]-48)) end select gosub OVERSPEED: '---------------------------------------------------------------------------------/ ' Here if the GPS module havent been fixed to any satellite will jump to notfix / '-------------------------------------------------------------------------------/ if fix = "V" then notfix ;pause 100 '-----------------------------------------------------------------------------/ ' [ Return from notfix ] / ' [ We clear any character on the display ] / '--------------------------------------------------------------------------/ 'serout2 lcd,6,[$45] 'Clear the ulcd 1'44 'pause 100 '-----------------------------------------------------------------------------/ ' Here we start the calendar conversion / '---------------------------------------------------------------------------/ arraywrite ndays,13,NDAY,[0,31,28,31,30,31,30,31,31,30,31,30,31] if ndays = 2 then if ((year//4 = 0) and (year//400 != 0)) then 'check the leap year ndays[2] = 29 'then February has 29 days else ndays[2] = 28 'else has 28 days endif endif hh = hh + 3 'the Hour from GPS is UTC so for our country in Greece we add +3 if hh>23 then 'if the hh+3 hour is greater than 23 (23:00) then day = day + 1 'we check the day added is true hh = hh//24 'but the hour not exceed the 24 so go to 00:00 if (day > ndays[month]) then month = month + 1 day = 1 if (month > 12) then year = year + 1 month = 1 endif endif endif '--------------------------------------------------------------------------/ ' here is where the code dispays the stored info from the NMEA sentenses / '------------------------------------------------------------------------/ HSEROUT2 [$73,$03,$00,$00,$FF,$FF," Protocol:","NMEA",$00] Hserin2 timeout,lostcable,[wait(6)] HSEROUT2 [$73,$01,$02,$01,$07,$E0," Date:",dec2 day,"/",dec2 month,"/",dec2 year,$00] Hserin2 timeout,lostcable,[wait(6)] HSEROUT2 [$73,$00,$04,$00,$FF,$E0," TIME: ",dec2 hh," :",dec2 mm," :",dec2 ss,$00] Hserin2 timeout,lostcable,[wait(6)] HSEROUT2 [$73,$00,$07,$00,$FF,$FF," Sats",$00] Hserin2 timeout,lostcable,[wait(6)] HSEROUT2 [$73,$01,$09,$11,$6D,$BF,dec2 satno,$00] Hserin2 timeout,lostcable,[wait(6)] HSEROUT2 [$73,$0E,$07,$00,$FF,$FF," Fixed",$00] Hserin2 timeout,lostcable,[wait(6)] HSEROUT2 [$73,$0B,$09,$11,$6D,$BF," ",fix," ",mode2d3d,"D",$00] Hserin2 timeout,lostcable,[wait(6)] HSEROUT2 [$73,$05,$06,$11,$FF,$E0," SPEED",$00] Hserin2 timeout,lostcable,[wait(6)] HSEROUT2 [$73,$06,$05,$12,$6D,$BF,TS[0],TS[1],TS[2],TS[3],$00] Hserin2 timeout,lostcable,[wait(6)] HSEROUT2 [$73,$06,$06,$12,$FF,$E0,"Km/h",$00] Hserin2 timeout,lostcable,[wait(6)] HSEROUT2 [$73,$00,$0C,$00,$ff,$ff," Lat : ",dec2 degrees,"*",dec2 minutes,"'",dec4 minutesd,"@"," ",$00] Hserin2 timeout,lostcable,[wait(6)] HSEROUT2 [$73,$BE,$0C,$10,$f8,$00,dir,$00] Hserin2 timeout,lostcable,[wait(6)] HSEROUT2 [$73,$00,$0E,$00,$ff,$ff," Lon :",dec3 degrees2,"*",dec2 minutes2,"'",dec4 minutesd2,"@"," ",$00] Hserin2 timeout,lostcable,[wait(6)] HSEROUT2 [$73,$BE,$0E,$10,$f8,$00,dir2,$00] Hserin2 timeout,lostcable,[wait(6)] goto main
See next the notfix label:Code:'---------------------------------------------------------------------------------/ ' Here if the GPS module havent been fixed to any satellite will jump to notfix / '-------------------------------------------------------------------------------/ if fix = "V" then notfix
As i do not use any interrupt at the moment, any instruction is waiting to be completed until the next one will continue.
So at this code, when i POWERUP the circuit, until the GPS gets the signal, jumps at the notfix.
QUESTION:Code:notfix: ' Still looking for fixed signal hh = hh + 3 hh = hh//24 HSEROUT2 [$73,$00,$03,$11,$6D,$BF," Waiting for GPS",$00] Hserin2 timeout,lostcable,[wait(6)] HSEROUT2 [$73,$00,$07,$00,$07,$ff,rep "." \dots,$00] Hserin2 timeout,lostcable,[wait(6)] HSEROUT2 [$73,$07,$09,$10,$6D,$BF,"SATs :",dec2 satno,$00] Hserin2 timeout,lostcable,[wait(6)] HSEROUT2 [$73,$04,$07,$12,$F8,$00,"NOT FIXED",$00] Hserin2 timeout,lostcable,[wait(6)] HSEROUT2 [$73,$06,$0D,$11,$6D,$BF,fix," ",mode2d3d,"D",$00] Hserin2 timeout,lostcable,[wait(6)] HSEROUT2 [$73,$03,$06,$10,$ff,$E0," Time:",dec2 hh," :",dec2 mm," :",dec2 ss,$00] Hserin2 timeout,lostcable,[wait(6)] pause 3000 HSEROUT2 [$45] ' clears the LCD Hserin2 timeout,lostcable,[wait(6)] goto main 'returns to main
Now, i need to clear at the end of the notfix the display, because if there is a FIX from the GPS, will go back to main, and i need to see the new data and not a mixed from notfix and main. Is there any way to clear the LCD before i go back to main without place the clear lcd command inside the main or the notfix label? ? Could you please help me and give me some advice?
Still i havent design any circuit as i develop the test board some things are changing.
I post pictures of the test board, and i would try to explain what i have done.
Last edited by astanapane; - 4th July 2018 at 10:49.
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Re: GPS Project: PIC18F26K22 or PIC18F46K22
A Test with an not very good ATTEN oscilloscope.
main:
high LED
pause 10
low LED
pause 100
goto main
With an Auto-trigger i get 9.11 Hz
If i make the following change
main:
high LED
pause 10
low LED
pause 50
goto main
i get a frequency of: 16.72 Hz.
As far as i have discussed with Ioannis, it should be ok, and the setting for 64Mhz is activated up and running.
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Re: GPS Project: PIC18F26K22 or PIC18F46K22
Obviously your picture shows the first piece of code. You Oscilloscope is set for 50ms/div, so your period seems to measure about 110ms.
Your program is making high for 10ms and another 100ms low which makes for a 110ms plus any PIC delays and inaccuracies, very much close to 120ms.
Good to go!
Ioannis
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