Data channel test apparatus and method thereof
View Patent ↗A system includes a plurality of devices that are connected in series and a controller that communicates with the devices. Each of the devices has a plurality of input ports and corresponding output ports. The outputs of one device and the inputs of a next device are interconnected. The controller is coupled to the first device and the last device of the series-connection. The controller applies a test pattern to the plurality of input ports at the first device connected in series, by the controller. Each data channel defines a data path between corresponding pairs of input and output ports of the first and last devices. A data channel is enabled if the test pattern is detected at its corresponding output port.
1. A method for enabling data channels in series-connected devices, the method comprising:
applying a test pattern to a plurality of input ports at a first device of the series-connected devices, the plurality of input ports having a corresponding plurality of output ports at a last device of the series-connected devices, each data channel defining a data path between corresponding pairs of input and output ports;
detecting an enabled data channel if the test pattern is received at its corresponding output port;
setting maximum data width for transmission based on the number of detected enabled data channels; and
configuring a data mode configuration register in each of the series-connected devices to indicate the maximum data width for transmission.
2. The method of claim 1 , further comprising:
upon detecting the enabled data channel, enabling corresponding use-state registers associated therewith in each of the series-connected devices.
3. The method of claim 2 , further comprising:
initializing use-state registers in each of the series-connected devices prior to applying the test pattern.
4. The method of claim 3 , wherein the use-state registers in each of the series-connected devices is initialized to indicate a disabled state.
5. The method of claim 1 , further comprising:
initializing device identifiers (IDs) in each of the series-connected devices prior to applying the test pattern.
6. The method of claim 5 , wherein the initializing device IDs comprises:
initializing the device IDs in each of the series-connected devices to a common value.
7. The method of claim 1 , further comprising:
simultaneously asserting an input port enable and an output port enable signal prior to applying the test pattern.
8. A device for use in a system including a plurality of devices connected in series and a controller, the device comprising:
a plurality of input connections and corresponding plurality of output connections;
a plurality of use-state registers associated with each of the corresponding input and output connections to indicate a use-state of the corresponding input and output connections; and
a data mode configuration register to indicate the maximum data width for transmission through the device.
9. The device of claim 8 , wherein a status of the plurality of use-state registers is set by the controller.
10. The device of claim 8 , wherein a status of the data mode configuration registers is set by the controller.
11. The device of claim 8 , wherein simultaneously asserting an input port enable signal and an output port enable signal causes the device to enter a test mode.
12. The device of claim 8 , further comprising:
a device ID register for holding a device ID associated with the device.
13. A controller for enabling data channels in a plurality of devices connected in series, the controller comprising:
a test pattern provider for providing a test pattern to a plurality of input ports at a first device of the plurality of devices connected in series, the plurality of input ports having a corresponding plurality of output ports at a last device of the plurality of devices connected in series, each data channel defining a data path between corresponding pairs of input and output ports of the first and last devices in a data channel test operation, the controller detecting enabled data channels if the test pattern is received at its corresponding output port, the controller setting maximum data width for transmission based on the number of detected enabled data channels and configuring a data mode configuration register in each of the plurality of devices connected in series to indicate the maximum data width for transmission.
14. The controller of claim 13 , further comprising:
a comparator for comparing the test pattern received at the plurality of the output ports to the test pattern provided to the plurality of input ports in the data channel test operation.
15. The controller of claim 13 , further comprising:
a plurality of controller use-state registers associated with each of the corresponding input and output ports to indicate a use-state of the corresponding input and output ports.
16. The controller of claim 15 , wherein the controller sets a status of the controller use-state registers and a status of a plurality of use-state registers in each of the devices.
17. The controller of claim 13 , wherein the controller further comprises:
a controller data mode configuration register to indicate the maximum data width for transmission through the series-connected devices.
18. The controller of claim 17 , wherein the controller sets a status of the controller data mode configuration register.
19. The controller of claim 13 , wherein the controller simultaneously asserts an input port enable signal and an output port enable signal causing the devices to enter a test mode.
20. A system comprising:
a plurality of devices, having a plurality of data channels, connected in series;
the plurality of devices having a plurality of input ports at a first device of the plurality of devices connected in series, the plurality of input ports having a corresponding plurality of output ports at a last device of the plurality of devices connected in series, each data channel defining a data path between corresponding pairs of input and output ports; and
a controller coupled to the plurality of input ports and the corresponding plurality of output ports,
the controller having a test pattern provider for providing a test pattern to the plurality of input ports in a data channel test operation, the controller detecting enabled data channels if the test pattern is received at its corresponding output port, the controller setting maximum data width for transmission based on the number of detected enabled data channels and configuring a data mode configuration register in each of the plurality of devices connected in series to indicate the maximum data width for transmission.
21. The system of claim 20 , wherein each of the plurality of devices connected in series further comprises:
a plurality of input connections and corresponding plurality of output connections, the plurality of the input connections of the first device of the plurality of devices connected in series defining the plurality of the input ports, and the plurality of the output connections of the last device of the plurality of devices connected in series defining the plurality of the output ports.
22. The system of claim 20 , wherein each of the plurality of devices connected in series further comprises:
a plurality of use-state registers associated with each of the corresponding input and output connections to indicate a use-state of the corresponding input and output connections.
23. The system of claim 22 , wherein the controller sets a status of the plurality of use-state registers of the plurality of devices connected in series.
24. The system of claim 20 , wherein the controller further comprises:
a comparator for comparing the test pattern received at the plurality of the output ports to the test pattern provided to the plurality of input ports in the data channel test operation.
25. The system of claim 20 , wherein the controller further comprises:
a plurality of controller use-state registers associated with each of the corresponding input and output ports to indicate a use-state of the corresponding input and output ports.
26. The system of claim 20 , wherein the controller further comprises:
a controller data mode configuration register to indicate the maximum data width for transmission through the plurality of devices connected in series.