Master and Slave LCD sim?

[RobertS]

I have a commercial circuit which uses a mask ROM mcu which receives and transmits data via the I2C bus. It receives data to display via a slave MCU and the master then transmits to the LCD driver controller to display dot matrix graphics.

The master MCU needs to be viewed as a "black box" since it is not possible code to view/disassemble (unless I am mistaken).

What I want to do is add my own slave MCU to the bus to display data when the master is not actively display text and graphics.

I hope to use Proteus ISIS to simulate communication between master mcu and LCD, and slave mcu and LCD via the I2c bus to help me learn and develop my idea. I would be using AVR Studio 4 to develop code using GNU GCC (WinAVR).

Is anyone aware of a project that I can simulate to help me on my way?
Thanks for your help.

 

[Papabravo]

Is the content of the I2C messages documented? If not I'd be in favor of going directly to the display.

 

[RobertS]

It's not documented, although there is the option to sniff and log all traffic and reverse engineer the protocol.

Your suggestion about going direct to the display driver would probably be less painful an exercise.

One question I have about this is how would the slave knows when when it is free to transmit or to wait? Is there a busy pin or similar the slave can poll?

When using the PG12864F LCD for example, is there a way to call up a data sheet for this device from Proteus ISIS to learn of pinout and programming?

EDIT: Ctrl-D should bring up the data sheet for the highlighted part, Proteus reports the sheet is not available however.

 

[Papabravo]

What exactly is Proteus ISIS and why are you relying on them for datasheets?
Follow the link:
**broken link removed**

 

[RobertS]

What exactly is Proteus ISIS and why are you relying on them for datasheets?
Its mixed mode simulation software

Follow the link:
**broken link removed**

Details are a bit sparse. I'm sure I could find it with Google but that wasn't my question.

 

[bananasiong]

Proteus ISIS is the simulation tool by labcenter.
http://www.labcenter.co.uk/index.cfm

RobertS,
Just search the datasheet from google for any device.