WS-400 is a device that connects to any of MERA-400 debug interfaces to display internal CPU and AWP states. You can see it in action here
After powering the device on, user selects the debug interface which WS-400 is connected to with SELECT button. Available connections are:
- CPU: P-X (l), P-M (r), P-P (r), P-R (r), P-A (l),
- AWP: FPA (l) FPA (r), FPM (l), FPM (r), FPS (l).
Connector location (either left or right) is denoted in parentheses. Selection is confirmed with OK button and WS-400 immediately starts displaying active signals. If all active signals don't fit on the screen, right pointing arrow appears on the bottom right. SELECT button can then be used to switch to next portion of active signals.
User can also switch to raw display mode at any time with OK button. In this mode SELECT button allows switching between 16-bit portions of the interface view.
Device can also be installed on the interface rotated 180 degrees in Z axis. This requires translation of signal, which is achieved by powering on or resetting the device with button OK pressed.