Serial Data Gateway w/HP2
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2008 GMC Yukon XL, 2008 GMC Yukon, 2008 Chevrolet Tahoe, 2008 Chevrolet Suburban, and 2008 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
The SDGM in this vehicle functions as a gateway or translator. The purpose of the gateway is to translate serial data messages between the high speed GMLAN serial data bus, the low speed GMLAN serial data bus, and the high speed hybrid GMLAN serial data bus for communication between the various modules. The gateway will interact with each network according to that network's transmission protocol.