Orion and Maia ADD2 Card User Guide
SiI
-UG-0044-A
4
Board Description
The basic block diagram of the Orion and Maia ADD2 cards is illustrated in Figure 3. Each block is briefly
explained below.
Figure 3. Functional Blocks of ADD2 Card
PCI-Express Connector:
The PCI-Express slot passes all SDVO signals including the 1MHz-speed 2.5V I
2
C bus from the Grantsdale G
chipset and SDVO signals, and returns INT# (Serial Interrupt) from the Si
I
1364 Tx. Both ADD2-N and ADD2-R
have x16 length PCI-Express card-edge connectors.
Configuration EEPROM
The Configuration EEPROM stores vital configuration header information for the Grantsdale G driver to recognize
and configure the Si
I
1364 Tx as an SDVO-based DVI device. The EEPROM I
2
C bus from the Si
I
1364 Tx
operates at 400kHz at 3.3V. The Si
I
1364 Tx has internal 3.3V pull-up resistors for this bus; therefore, no external
pull-up resistors are stuffed. All ADD2 cards are shipped with a pre-programmed EEPROM installed. Refer to the
Bill of Materials for additional EEPROM information.
Si
I
1364 Tx and I
2
C Circuits
The Si
I
1364 Tx is the device that links the Grantsdale G platform to a DVI flat panel display. Grantsdale G reads
the EDID of a connected display, or retrieves configuration information from the EEPROM, by way of the I
2
C
pass-through of the Si
I
1364 Tx. This pass-through interface operates at a 100kHz rate and provides the
required level shifting from the 2.5V Grantsdale G interface to either the 3.3V EEPROM interface or the 5V DDC
interface. The Si
I
1364 Tx also provides an interrupt signal to the Grantsdale G to signal a display attach/detach
event using the DVI Hot Plug function.
