Sending text to GLCD using BV4511 interface

[Tabsoft]

It may be that the controller is programmed with a different I2C address.

Here is a I2C Buss Scan program that Darrel Taylor created.
I have modified it to suit my HW setup.
I have used this many times very effectively.

Maybe you can use this to scan the I2C Buss to determine the Address of the controller.

I2CSearcher.txt

Don't forget to change the file extension back to .bas or .pbp.

I would use this to scan the buss and see if it shows up.
If not, if you have a scope you can check the buss and see if it is working correctly.

Lastly, the DS has a procedure to default the controller, you may want to try that as a last resort.

[Scampy]

Thanks for the test code. I've changed the parts to suit the PIC and Easypic board and compiled it without error.

I am currently working on a project and have a breadboard with an DS1307 RTC chip connected to the EasyPIC5 board via the expansion port. On running the application it reported one device found and it's default address that matched that used in the project code. I then connected the GLCD and double checked the wires were correctly connected to the i2C bus. Upon running the PIC again (twice to be sure) I got the attached results !!

I have no idea what's happening... my guess it that the board contains firmware that will only respond to serial codes or similar and not a normal i2c protocol - Resetting the board using the jumper wire has had no affect...

[Tabsoft]

Could you try this?

Modify the test code to print out the "Response" value coming back from the controller.
E.g HEROUT [HEX2 Addr, " ", HEX2 Response, 13, 10]

Then this?
I2Cwrite SDA, SCL, $68, [$1b, "[", 1, ";", 1, "H"]
I2Cwrite SDA, SCL, ["hello"]

[Scampy]

I found a similar sketch to test the i2c bus for an arduino.

/ This sketch tests the standard 7-bit addresses
// Devices with higher bit address might not be seen properly.

When polled it reported one device found at 0x21

I have no idea why when I do the same with the PBP code it reports 128 devices found at all the even addresss (0,2,4,6,8,0A,0C etc etc)

[Tabsoft]

In the I2C search portion of the program do you have the ", NoAck" and the NoAck label?

I2Cread SDA, SCL, ADDR, [Response], NoAck
Blah
Blah
Blah

NoAck:
Next ADDR

The ", NoAck" portion makes the I2Cread command wait for an ACK from the device. If an ACK is NOT received it jumps to the NoAck label where the ADDR variable is incremented. If an ACK IS received then the SlaveCount variable is incremented and the address is output telling you that that address responded.

Also, do you have the DEFINE I2C_HOLD 1 statement still in there?
The controller may need this clock stretching support.

[Scampy]

Errr... No not used the NoAck

To be honest given all this hassle and the way the datasheets don't help, I'm going to look for another device. I picked this up from e-bay for £12 (half the price of the current model) so I've not wasted a huge amount of cash.

I appreciate you help

Malcolm

[Tabsoft]

Oops.

Yep, without the NoAck all even numbered addresses will report found because you're not testing for the ACK, which is exactly what it reported finding 128 devices.