Issue with AXE133Y Serial OLED

[Gramps]

Strange characters appearing on the OLCD.
Could I have accidentally erased the code on the OLCD chip?

 

[bfgstew]

Try adding in your init routine -
serout B.7, N2400, (254, 1)
pause 100

And do away with the 2 lines, just use -
serout B.7, N2400,(254,128"hi world!")

 

[Gramps]

init: pause 500
main:
serout B.7, N2400,(254,128"hi world!")
pause 100
end

Editor says "Syntax error.........."

 

[hippy]

Editor says "Syntax error.........."

bfgstew missed a comma out, perhaps due to the lateness of the hour. If you look at the command the Syntax Error refers to you should be able to figure out where that comma should be added. If not -

serout B.7, N2400,(254,128 , "hi world!")

 

[bfgstew]

Thanks hippy......late hour.....early start!

 

[Gramps]

Okay hooked everything up and ran bfgstew's code nothing happens. OLCD does not light.
How to reload the code on the picaxe chip that piggybacks the OLCD? I'm sure I messed up that code trying to add something to that chip.

 

[bfgstew]

Ok will ask the usual.
Post exact code.
Pre made OLED or did you assemble it? If so post pic of connections.
Circuit diagram.
OLED connected to B.7 as per code.
Give as much info as you can please.

 

[darb1972]

Gramps, you can get the firmware here;

http://www.picaxe.com/Hardware/Add-on-Modules/Budget-Serial-OLED-Module/

Download. Put into the editor. Load into the piggyback board.

 

[Gramps]

Thanks , Darb!
Reloaded firmware, booting correctly!
Hi bfgstew,
To answer your questions, yes I assembled it, yes, it worked after it was assembled.
As I thought, we crashed the firmware. Restoring firmware, it is now operating correctly again.
Showing first line, "Serial OLED" Second line, "ww.picaxe.com"
Loading your code. Compiles correctly but no change in the OLED output.
I think the problem is we can't find the B.7 pin on the revolution 28 pin project board. We tried both pin 7's and neither one changes the OLED.
The specs that came with the board are not labeled B.1, B.2 etc.

 

[eclectic]

snip
I think the problem is we can't find the B.7 pin on the revolution 28 pin project board. We tried both pin 7's and neither one changes the OLED.
The specs that came with the board are not labeled B.1, B.2 etc.

Please see

http://www.picaxe.com/docs/picaxe_manual1.pdf

page 34 for guidance.

Pins and Legs have different meanings in "Picaxe-Speak"
e

 

[Aries]

Lay the project board with the download socket on the top edge.
B.7 is the top right pin on the 28X2
This connects to the top right on the output side. This is labelled 7 B on my board project board
You can check the connection with a multimeter

 

[Gramps]

This is the 28 pin project board. The left side and the right side of the board are labeled pins 7 through 0. We connected the OLED to each pin 7 and reset the board. "Hi world" did not appear
Aries, your post came in after this one we will check it out

 

[eclectic]

@Gramps. Did you
also see post #10 ?

e

 

[Gramps]

Yes, the diagram says leg 28 is B. 7
Ok, when we connected the OLED to the actual leg 28 on the picaxe, which by the way is not labeled, " hi World "appeared!
Apparently the chip between the picaxe and pin 7 in the lower left corner of the project board somehow does not allow the signal to reach the OLED

 

[hippy]

This is the 28 pin project board. The left side and the right side of the board are labeled pins 7 through 0

You appear to be connecting to the Darlington Driver output. You need to connect to the PICAXE pin before it passes into the Darlington Driver; connect to the header pins between the two.

 

[Gramps]

Are the Darlington drivers designed to handle more amperage then the picaxe?

 

[westaust55]

Yes.

However the ULN2803 and similar are open collector Output and also invert the signal. A PICAXE high output drives the Darlington / ULN2803 output low. When the PICAXE output is low then the ULN2803 output is floating.

Hence you need to connect directly to the PICAXE pin.

 

[Gramps]

Okay, that explains why we had to reverse polarity on the LEDs that were connected to the Darlington chip in order to get them to light .

 

[Gramps]

Success! We were able to copy and paste bfgstew's code to the Editor and load it to the 28 pin picaxe using the serial cable on the new computer.!!!
It installed on comport 4

 

[Gramps]

Our new breadboard featuring a parallax prop power supply and our now functioning OLED!

 

[darb1972]

Good work Gramps. It's an awesome feeling when a project (or experiment) finally works isn't it? Very satisfying.

Not there yet, but Happy New Year to you too!!!

 

[Gramps]

Ya, this Bread board is running on the new computer finally set up with editor 6.
It's kind of a relief just to get all the hardware to work!