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georgestheking
Newbie

Joined: 21/12/2021
Location: Belgium
Posts: 32

Posted: 10:31am 21 Jan 2022

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Hi,

I make this to read a GY-26 compass :

REM-------------------------
REM PICOMITE 5.0703
REM -----------------------

option default integer
option explicit

DIM INTEGER RDATA(8)

SETPIN GP2,GP3, I2C2

sub compass

I2C2 OPEN 100, 1000
I2C2 WRITE &HE0, 0, 1, &H31 ' send read command &h31
I2C2 READ &HE1, 0, 8, RData() ' read 8 datas registers
I2C2 CLOSE

end sub

DO
compass

print rdata(0)
print rdata(1)

PAUSE 1000
LOOP

END

but i get an error : "pin not set for I2C2"

I use version 5.0703

Best regards

Georges

thwill

Guru

Joined: 16/09/2019
Location: United Kingdom
Posts: 4311

Posted: 10:36am 21 Jan 2022

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IIRC

I2C2 CLOSE

releases the pins, so the second time you enter compass() they are not set. To resolve move the SETPIN into compass() or the OPEN/CLOSE out of compass().

Best wishes,

Tom

MMBasic for Linux, Game*Mite, CMM2 Welcome Tape, Creaky old text adventures

TassyJim

Guru

Joined: 07/08/2011
Location: Australia
Posts: 6283

Posted: 10:51am 21 Jan 2022

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It looks like you have included the read/write bits in the address: E0 and E1

Just use the 7bit address and MMBasic adds the required direction bit

VK7JH
MMedit

georgestheking
Newbie

Joined: 21/12/2021
Location: Belgium
Posts: 32

Posted: 10:53am 21 Jan 2022

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Tom,

Thanks, no more error.

But I get 0,0.
Has anybody experience with the GY-26 compass ?

Best regards

Georges

georgestheking
Newbie

Joined: 21/12/2021
Location: Belgium
Posts: 32

Posted: 02:11pm 21 Jan 2022

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Thanks Jim,

The code is now :

Rem -------------------------
Rem PICOMITE 5.0701
Rem -----------------------

Option default integer
Option explicit
Dim INTEGER RDATA(8)

Rem COMPASS GY-26
Sub compass

SetPin GP2,GP3,I2C2

I2C2 OPEN 100,1000
I2C2 WRITE &HE0,0,2,0,&H31 ' send read command &h31
I2C2 READ &HE0,0,8,RData() ' read 8 registers
I2C2 CLOSE

End Sub

DO
compass

print rdata(1)
print rdata(2)

PAUSE 1000
LOOP

But still return 0,0 !!!

Best regards

Georges

PS : pull up resistors are in the right place

thwill

Guru

Joined: 16/09/2019
Location: United Kingdom
Posts: 4311

Posted: 02:26pm 21 Jan 2022

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You do know that the first element of rdata is rdata(0) don't you, unless you specify OPTION BASE 1 ?

MMBasic for Linux, Game*Mite, CMM2 Welcome Tape, Creaky old text adventures

Volhout
Guru

Joined: 05/03/2018
Location: Netherlands
Posts: 5089

Posted: 02:29pm 21 Jan 2022

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Hi george,

You should use the 7 bit I2C address.
The &hE0 is an 8 bit address, use &h70 in stead.

Volhout

PicomiteVGA PETSCII ROBOTS

JohnS
Guru

Joined: 18/11/2011
Location: United Kingdom
Posts: 4044

Posted: 02:29pm 21 Jan 2022

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Seen TassyJim's post?

John

georgestheking
Newbie

Joined: 21/12/2021
Location: Belgium
Posts: 32

Posted: 02:32pm 21 Jan 2022

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Woaww

It work now !

Many thanks Volhout,
I spent a complete day with this problem.

Best regards

Georges

georgestheking
Newbie

Joined: 21/12/2021
Location: Belgium
Posts: 32

Posted: 02:44pm 21 Jan 2022

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Thanks to the complete team for the help,

The right code:

Rem -------------------------
Rem PICOMITE 5.0703
Rem -----------------------

Option default integer
Option explicit

Dim As INTEGER RDATA(8)
Dim As integer P,R

Rem COMPASS GY-26
Sub compass

SetPin GP2,GP3,I2C2

I2C2 OPEN 100,1000
I2C2 WRITE &H70,0,2,0,&H31 ' send read &h31
I2C2 READ &H70,0,8,RData() ' read 8 registers
I2C2 CLOSE

End Sub

Do

compass

R=rdata(1)*256+rdata(2)
Print R

Print

Pause 1000
Loop

End
Edited 2022-01-22 00:45 by georgestheking

lizby
Guru

Joined: 17/05/2016
Location: United States
Posts: 3378

Posted: 02:59pm 21 Jan 2022

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Glad you got it working. Note that the customary way to show code in a post is to include it within the forum tags "[ CODE]" and "[ /CODE]" (without the quote marks and without the space following "[".

Like this:

Rem -------------------------
Rem PICOMITE 5.0703
Rem -----------------------

Option default integer
Option explicit

Dim As INTEGER RDATA(8)
Dim As integer P,R

Rem COMPASS GY-26

Sub compass
SetPin GP2,GP3,I2C2

I2C2 OPEN 100,1000
I2C2 WRITE &H70,0,2,0,&H31 ' send read &h31
I2C2 READ &H70,0,8,RData() ' read 8 registers
I2C2 CLOSE
End Sub

Do
compass
R=rdata(1)*256+rdata(2)
Print R
Print
Pause 1000
Loop

End

Note that this preserves indentation if your code has any.

PicoMite, Armmite F4, SensorKits, MMBasic Hardware, Games, etc. on fruitoftheshed

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