This utility is a bridge server for high performance, push based access to raw waveform data on Teledyne LeCroy oscilloscopes which have the XDEV software option installed.
It provides a TCP server on port 1862 which supports one client at a time.
If you are using the "lecroy_fwp" driver in libscopehal to talk to this bridge, all instrument-side configuration is automatic. Simply start the bridge server on the oscilloscope and the driver will configure the FastWavePort blocks as needed.
Maximum supported memory depth using the current FastWavePort backend is 40M points per channel. If we switch to FastMultiWavePort in the future, this limitation will be removed however limited documentation has made this difficult so the initial implementation uses FastWavePort.
Clients may subscribe to up to four analog channels worth of data. Digital channels and 8-channel scopes are not currently supported.
To update your set of subscriptions, send a single byte to the server. The high nibble is ignored; the low nibble is treated as a bitmask where 1 = channel 1, 2 = channel 2, 4 = channel 3, 8 = channel 4. A high in each bit position indicates the client is interested in data from this channel and a 0 indicates it is not interested.
Each time the scope triggers, the server sends a two part data block to the client consisting of a fixed sized header and variable sized per-channel waveform data.
The header consists of four consecutive CDescHeader structures (as documented in the "Fast Wave Port Function" section of the Teledyne LeCroy Advanced Customization Instruction Manual) for channels 1-4 in sequence. If a channel is subscribed, the CDescHeader block will contain the raw waveform headers as provided via FastWavePort. If the channel is inactive, an all-zeroes CDescHeader is sent instead as a placeholder.
After the headers, each channel's data is sent. The data block consists of header.numSamples signed 16-bit integers, and is copied verbatim from the FastWavePort shared memory without any preprocessing.
This server must be run on the oscilloscope itself, since it uses Windows shared memory to communicate with MAUI. A FastWavePort math function must be configured for each active channel; the port name for the math function must be "FastWavePortN" where N is the channel number.
Any math channel may be used for the FastWavePort blocks; the "lecroy_fwp" driver in libscopehal uses F9-F12. Note that the FastWavePort function is synchronous and will block until a timeout elapses; it is thus important to ensure that the set of enabled FastWavePort math channels matches the set of channels the client is subscribed to (since scopehal-fwp-bridge only acknowledges data on active channels). The "lecroy_fwp" driver manages this automatically but if you are writing custom client software it will be necessary to send SCPI or Automation commands to the instrument to do this.