In A hurry? Having trouble with SpaceWire? Need to get to the bottom of your interconnect issue fast? DESWBO will help you to solve SpaceWire link issues. With DESWBO - Dynamic Engineering SpaceWire BreakOut - Spacewire can be interconnected and monitored. DESWBO has two 9-pin MDM connectors to facilitate in-line monitoring of both sides of a SpaceWire link. DESWBO is designed to detect and decode bit sequences. Signals are issued indicating what types of characters are passing between nodes as well as the contents of data and timecode characters. A running count of flow control credits for each node is calculated by the DESWBO by monitoring FCTs and N-character occurrences. LED and testpoint based user interface. Stand-alone operation. Power Supply included. Cables available.
The Dynamic Engineering SpaceWire Break-Out (DESWBO) monitors the signals of a single SpaceWire link. The board has two 9-pin MDM connectors to facilitate in-line monitoring of both sides of a SpaceWire link. DESWBO is designed to detect and decode bit sequences. Signals are issued indicating what types of characters are passing between nodes as well as the contents of data and timecode characters. A running count of flow control credits for each node is calculated by the DESWBO by monitoring FCTs and N-character occurrences.
The LVDS signals from each node are buffered to the opposite node and monitored by an FPGA. The FPGA contains the equivalent of two SpaceWire receiver modules that decode the SpaceWire signals, and extract the various data and control characters. See block diagram below. The DESWBO is tested with a special version of the PCI-SpaceWire with the ability to insert errors under software control. Normal and error conditions are tested on each unit as part of the ATP.
DESWBO Block Diagram
The end-of-packet, got-data and got-fct signals from each node are connected to pulse capture and extension circuits to drive three green LEDs. The error-end-of-packet, parity error, escape error, credit error and disconnect error signals for each node drive five red LEDs. These sixteen LEDs give a quick status of link activity and health.
In addition there are 24 test points for each node that are driven by the real-time signals from the SpaceWire character receivers, two test points for each node that are connected to the DIN and SIN signals from the LVDS receivers and one test point for each node that is driven by the recovered clock from the SpaceWire bit receivers.
The 24 test point signals consist of eight data bits, six credit count bits, Parallel data strobe, NULL received, FCT received, Timecode received, End-of-Packet, Error End-of-Packet, Credit error, Disconnect error, Escape error and Parity error. In addition there are three ground test points per node to facilitate probe grounding.
The DESWBO is powered by an external 5-volt supply [included] with on-board regulators for the various operating voltages required.
