Would be cool if the propeller chip could talk to the monitor using DDC. Anyone

Kye

I'll write a simple I2C driver for this if anyone knows how the eletrical interface works. The regular I2C pins even could be used so that no extra pins would be wasted.

I tried hooking the monitor up before once, but it disabled the prop chip's ability to use the I2C lines last time I did this. So again, anyone know how to interface the devices and what the vga·monitor's I2C·addresses are?

I'm thinking it would be kinda cool to have.



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Nyamekye,

Post Edited (Kye) : 10/17/2009 10:05:42 PM GMT

Kye

No ones knows about this? Mmm...

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Nyamekye,

jazzed

The address seems to be 0x50. Try these links:
www.hardwarebook.info/VGA
en.wikipedia.org/wiki/Extended_display_identification_data

Bob Lawrence (VE1RLL)

One Example:


Prior to the DDC, the VGA standard had reserved three pins, known as ID0, ID1, and ID2 (pins 9, 12, and 15) for identification of monitor type. The pins, attached to resistors to pull one or more of them high, allowed for the definition of up to seven monitor types, with all zero meaning "no monitor". However, only three types of monitor were defined - monochrome with a resolution of less than 1024

Bob Lawrence (VE1RLL)

The maximum pull-up resistor should also be sized such that the RC time constant meets
the standard I2C-bus rise time, which is 1 ms for Standard-mode (100 kHz) or 300 ns for
Fast-mode (400 kHz). DDC bus complies with the I2C-bus Standard-mode and operates
below 100 kHz, and maximum rise time is 1 ms using a simplified RC equation.

Note taken from this doc:

www.nxp.com/acrobat_download/datasheets/PCA9507_1.pdf

evanh

Small m is the abbreviation for milli. It's common to use a small u for micro, ie: 1us.