Single Board Computer The single board computer (SBC) is the main processor in the system. See (Figure ) showing the board layout. The TCP/IP network interface connects directly to the RJ-45 connector on the SBC. The network interface supports both 10baseT and 100baseT operation. The hardware differentiates automatically. There are two LED’s at the RJ-45 connector. These show the status of the network connection as follows: • Green LED: Indicates there is a network connection present. • Amber LED: Indicates there is a network communication. The Hard Disk Drive (HDD) connects to the SBC with a standard IDE interface (ribbon cable).
The HDD contains the Linux operating system and all the control software needed to run the system (except the controller firmware). This is also where all the downloaded models are stored in the queue. The LCD Control Panel connects to the I/O Card. The signals then travel though the PDB and on to the SBC. All user entered commands from the control panel buttons are routed through the I/O and PDB and then on to the SBC. The P104 connector on the top edge of the board is a bus level interface to the controller board. This allows the SBC to read and write to the dual port ram on the controller board, which forms the communication channel between the two boards. Figure 2:
Single board computer detail Display Panel DB-9 Connector RJ-45 Network Connector SATA Connector P104 Connector J2 power input -7