The standard VIA interface for both SBC-2 and SBC-3 are two 14-pin headers. These contain either Port A or Port B pins, the two handshake pins, and +5V and ground pins. They are separated with enough room to mount two IDC ribbon cable headers - allowing for each port to be connected to different devices. Alternatively, a larger IDC header can be placed on both pin headers to allow for all VIA pins to be connected to one device. All of the devices listed under this section use these VIA ports.
Here's the pin layout: