What signal connections or I/O interfaces can Sealevel design into a COM Express carrier board?

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COM Express is the most commonly used Computer on Module implementation. Although there are three different sizes and other technical variations, the Basic size (125 x 95mm) and Type 2 pin out configuration are the most widely used and will work for most applications.

The Type 2 COM Express pin out provides a number of high speed buses to the carrier board including PCI Express, PCI, VGA, SCDO, IDE, SATA, Ethernet, USB, LPC and more. These signals are used in Sealevel carrier board designs to create optimized, custom solutions that provide the application-specific I/O, connector layouts and mechanical configurations for target applications.

The signal buses and capacity on Basic sized Type 2 modules include:

Bus Signals Capacity & Usage
PCI Express Up to 22 lanes for PCI Express devices. Can provide additional I/O expansion via FPGA and Sealevel IP.
PEG / SDVO PCI Express Graphics supporting up to 16 lanes dedicated to video; or Serial Display Video Out via a dedicated I2C channel. Can provide HDMI, DVI and DisplayPort interfaces.
PCI A single 32-bit port 33/66MHz interface for PCI devices.
SATA Up to four SATA channels that support 150 – 300Mb transfer.
IDE A single Parallel ATA100 (PATA) interface for mass storage devices.
LAN A single 10/100/1000 Base-T Gigabit Ethernet port. Carrier board can include additional LAN ports via PCI Express.
USB Up to 8 USB 2.0 ports. Can provide additional USB ports on carrier board via USB hub chips.
LPC Low Pin Count Bus for legacy I/O expansion. Ideal for adding serial, parallel, floppy, keyboard and mouse via Super I/O controller.
AC’97 / HDA Audio Codec 1997 specification; or High Definition Audio for 16-bit stereo audio output.
Speaker Out A single PC-AT speaker signal for system beeps and chirps.
VGA A single analog video output via dedicated DDC. Resolution dependent upon embedded graphics capability of COM Express module. Can provide additional VGA interfaces on carrier board via PCI Express.
LVDS Low Voltage Differential Signaling with dual-channel interface for very high bandwidth displays.
TV Out For NTSC/PAL standard video output. Supports Component, S-Video, or Composite video interfaces.
I2C Inter-Integrated Circuit. A single dedicated I2C channel for low speed system communications.
SMBus Generic processor interface via I2C for System Management Bus.
GPIO 8-bits of General Purpose I/O for software configurable interfaces.
ExpressCard Two ExpressCard interfaces for mobile computing and hot-swappable peripheral cards.
Watchdog A single watchdog timer for system reset logic and recovery.