I have developed an interface board to receive VGA data and output to RGB888
(24 bit RGB digital data). I am having an issue where the I2C appears to be
programming the device correctly but read-back does not appear to work. I have
worked on this for the last few days and thought that several things could be
wrong. First, I connected TEST0 and TEST1 per the evaluation board design of
the 7403. I have since disconnected these lines and there is no change. I
have modified my I2C pullups and series resistors and this has not had an
impact. When I write data, the device acknowledges on the 9th bit correctly.
When I read data, I get the slave acknowledge up and until I begin to generate
clocks and perform a master acknowledge to the device. The device appears to
not be giving any data back. I also know that through the configurations I
have programmed, the pixel clock should be specific frequencies (65MHz, 75MHz,
etc.). I have confirmed that these frequencies are in place so I am certain
that the device is operational. I am just uncertain as to why it appears to be
block from the reads. I am using a PIC 32MX795F512L with integrated I2C
peripheral to talk. Any help would be greatly appreciated.