GPS Project: PIC18F26K22 or PIC18F46K22

[richard]

if you are using the 16 bit baudrate generator
BAUDCON2.3 = 1 ' Enable 16 bit baudrate generator


then the baud rate is set using SPBRGHx and SPBRGx



setting

SPBRG2 = 160 ' 38400 Baud @ 64MHz, -0,08%

is only half the job

[astanapane]

if you are using the 16 bit baudrate generator
BAUDCON2.3 = 1 ' Enable 16 bit baudrate generator


then the baud rate is set using SPBRGHx and SPBRGx



setting

SPBRG2 = 160 ' 38400 Baud @ 64MHz, -0,08%

is only half the job

I will check the code later today based on your given directions. thanks a lot.

I might need to check and wait for the GPS responds and PIC port response. I will try to set a code, and if i need again your help i will keep you posted.

[astanapane]

Dear all,

i did the following....

'*-----------------------------------------------------------------------------|
'*                        |  --------------------- |                           |
'*----------------------- | EUART 1 Configuration  | --------------------------|
'*                        |  --------------------- |                           |
'*-----------------------------------------------------------------------------|
        
        RCSTA = $90 ' Enable serial port & continuous receive
        TXSTA = $24 ' Enable transmit, BRGH = 1
        'CLROERR = 1 ' Clear overflow automatically
        SPBRG = 160 ' 38400 Baud @ 64MHz, -0,08%
        SPBRGH = 1
        BAUDCON.3 = 1         ' Enable 16 bit baudrate generator
        
'*-----------------------------------------------------------------------------|
'*                        |  --------------------- |                           |
'*----------------------- | EUART 2 Configuration  | --------------------------|
'*                        |  --------------------- |                           |
'*-----------------------------------------------------------------------------|

        RCSTA2 = $90 ' Enable serial port & continuous receive
        TXSTA2 = $24 ' Enable transmit, BRGH = 1
        'CLROERR2 1 ' Clear overflow automatically
        SPBRG2 = 130 ' 9600 Baud @ 64MHz, -0,02%
        SPBRGH2 = 6
        BAUDCON2.3 = 1         ' Enable 16 bit baudrate generator
        

'------------------------------------------------------------------------------|
'-----------sent a sentence to gps, this is not working at the moment----------|
'------------------------------------------------------------------------------|
' When the GPS Module is POWERED ON, then the following sentenses are received. 

'          $PMTK011,MTKGPS*08
'          $PMTK010,001*2E
'          $PMTK010,002*2D   

pause 800 
HSEROUT2 ["$PMTK251,38400*27",13,10]      ' 38400 boundrate, check MTK manual configuration
pause 800

SPBRG2 = 160 ' 38400 Baud @ 64MHz, -0,08%
Pause 500

HSEROUT2 ["$PMTK220,100*2F",13,10]        ' 100(millisecond)=0.1(sec)-->1/0.1= 10Hz
pause 100

It works the part of a baudrate change, when i send the command to the gps

HSEROUT2 ["$PMTK251,38400*27",13,10]      ' 38400 boundrate, check MTK manual configuration
pause 800

but i think the following it goes to GPS but for some reason is not set.

HSEROUT2 ["$PMTK220,100*2F",13,10]        ' 100(millisecond)=0.1(sec)-->1/0.1= 10Hz
pause 100

[tumbleweed]

When you switch the baudrate you have to set both SPBRG2 and SPBRGH2.

Try:

SPBRG2 = 160 ' 38400 Baud @ 64MHz, -0,08%
SPBRGH2 = 1
Pause 500

[astanapane]

When you switch the baudrate you have to set both SPBRG2 and SPBRGH2.

Try:

SPBRG2 = 160 ' 38400 Baud @ 64MHz, -0,08%
SPBRGH2 = 1
Pause 500

It worked!!! I will post later on what i have done up to now. Maybe i need to set up a small indication when those commands are set. So i know that program is working up to that stage.

This is the code for changing the baudrate to GPS and the hz rate at 10Hz at the NMEA data.

'*-----------------------------------------------------------------------------|
'*                        |  --------------------- |                           |
'*----------------------- | EUART 1 Configuration  | --------------------------|
'*                        |  --------------------- |                           |
'*-----------------------------------------------------------------------------|
        
        RCSTA = $90 ' Enable serial port & continuous receive
        TXSTA = $24 ' Enable transmit, BRGH = 1
        'CLROERR = 1 ' Clear overflow automatically
        SPBRG = 160 ' 38400 Baud @ 64MHz, -0,08%
        SPBRGH = 1
        BAUDCON.3 = 1         ' Enable 16 bit baudrate generator
        
'*-----------------------------------------------------------------------------|
'*                        |  --------------------- |                           |
'*----------------------- | EUART 2 Configuration  | --------------------------|
'*                        |  --------------------- |                           |
'*-----------------------------------------------------------------------------|

        RCSTA2 = $90 ' Enable serial port & continuous receive
        TXSTA2 = $24 ' Enable transmit, BRGH = 1
        'CLROERR2 1 ' Clear overflow automatically
        SPBRG2 = 130 ' 9600 Baud @ 64MHz, -0,02%
        SPBRGH2 = 6
        BAUDCON2.3 = 1         ' Enable 16 bit baudrate generator
        

'------------------------------------------------------------------------------|
'-----------sent a sentence to gps, this is not working at the moment----------|
'------------------------------------------------------------------------------|
' When the GPS Module is POWERED ON, then the following sentenses are received. 

'          $PMTK011,MTKGPS*08
'          $PMTK010,001*2E
'          $PMTK010,002*2D   

pause 800 
HSEROUT2 ["$PMTK251,38400*27",13,10]      ' 38400 boundrate, check MTK manual configuration
pause 800

SPBRG2 = 160 ' 38400 Baud @ 64MHz, -0,08%
SPBRGH2 = 1
Pause 500

HSEROUT2 ["$PMTK220,100*2F",13,10]        ' 100(millisecond)=0.1(sec)-->1/0.1= 10Hz
pause 100

[astanapane]

Dear all,

i need you help.

After removing all the DEFINEs and use only the following

'RCSTA2 = $90 ' Enable serial port & continuous receive
'TXSTA2 = $24 ' Enable transmit, BRGH = 1
'DEFINE HSER_CLROERR2 1 ' Clear overflow automatically
'SPBRG2 = 130 ' 9600 Baud @ 64MHz, -0,02%
'SPBRGH2 = 6
'BAUDCON2.3 = 1         ' Enable 16 bit baudrate generator

and for changing the baudrate and the frequency for the Second Serial,

pause 800 
HSEROUT2 ["$PMTK251,38400*27",13,10]      ' 38400 boundrate, check MTK manual configuration
pause 800

SPBRG2 = 160 ' 38400 Baud @ 64MHz, -0,08%
SPBRGH2 = 1
Pause 500

;HSEROUT2 ["$PMTK314,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,1,0*29",13,10]
HSEROUT2  ["$PMTK314,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0*28",13,10]
pause 100

HSEROUT2 ["$PMTK220,100*2F",13,10]        ' 100(millisecond)=0.1(sec)-->1/0.1= 10Hz
pause 100

I found out that on SERIAL TERMINAL on the computer of course i see the data coming from the GPS but unfortunately when i connect an LCD to PIC using the first Serial, the data cannot be displayed.

It seems that when i use

HSERIN2[wait("$GPRMC")

the data cannot be read from the GPS to the RX of the PIC.

I tried to check if there is a problem with the LCD, but i can send text to the LCD.

I tried to check and use only the DEFINEs with 9600 because the default for the GPS is 9600 and it worked.

so when i do not use the defines, it looks like that RX port on the PIC doesnt work.

Could you please help?

[Ioannis]

I don't know about other members of the forum, but I got confused.

Best throw in both codes that work and don't work.

Do they compile OK?

Are you sure about your connections?

Ioannis