morgendagen/riden-dongle

Purpose and deployment

Riden Dongle is ESP-12F/ESP8266 firmware replacing the stock Riden WiFi-module software. It bridges a Riden DC power supply’s UART Modbus RTU interface to LAN protocols: Modbus TCP, SCPI raw socket/VXI-11, and an embedded control/configuration web UI. PlatformIO builds the device firmware; the application entry point is src/main.cpp, with target configuration in platformio.ini.

Bootstrap and orchestration

src/main.cpp owns firmware lifecycle: hardware/network initialization, service startup, and periodic device-facing work. It composes the protocol, configuration, HTTP, and discovery/time capabilities rather than exposing a separate host application. Public component contracts are under include/, including include/riden_config/riden_config.h and include/riden_modbus/riden_modbus.h.

Device bus and canonical PSU access

src/riden_modbus/riden_modbus.cpp implements the Modbus RTU client that communicates with the physical Riden PSU over UART. Register definitions and device-model semantics are centralized in include/riden_modbus/riden_modbus_registers.h. This is the core hardware boundary: all remote protocols ultimately read/write PSU state through this layer, constrained by UART baud rate, Modbus address, and the PSU firmware’s register behavior.

Modbus TCP bridge

src/riden_modbus_bridge/riden_modbus_bridge.cpp translates inbound Modbus TCP requests into the local RTU/register operations. Its interface is include/riden_modbus_bridge/riden_modbus_bridge.h. This path preserves standard Modbus client compatibility while isolating network request handling from serial-device access.

SCPI and instrument transports

src/riden_scpi/riden_scpi.cpp maps SCPI commands and queries to PSU operations, with its public API in include/riden_scpi/riden_scpi.h; supported command surface is documented in SCPI_COMMANDS.md. src/scpi_bridge/scpi_bridge.h adapts transport input to that SCPI engine. Raw SCPI socket service and VXI-11 are mutually constrained at runtime: VXI-11 provides synchronous RPC-style instrument access, while raw socket supplies TCP port-5025 VISA compatibility.

VXI-11 RPC server

src/vxi11_server/vxi_server.cpp implements the VXI-11 instrument server, with RPC framing in src/vxi11_server/rpc_packets.cpp and port-mapper/binder behavior in src/vxi11_server/rpc_bind_server.cpp. This boundary exposes SCPI to VISA clients using TCPIP::<host>::INSTR, and participates in mDNS-based LAN discovery. The subsystem’s local design notes are in src/vxi11_server/README.md.

HTTP UI, configuration, and operations

src/riden_http_server/riden_http_server.cpp serves the embedded web interface for PSU status/control, graphs, device configuration, reboot actions, and OTA update flow. Static browser content is compiled into src/riden_http_server/http_static.h; source/mock UI artifacts live in src/riden_http_server/html_content/. HTTP routes invoke the same PSU/configuration services as the machine protocols, making the UI another client boundary rather than a separate control plane.

Persistent configuration and external services

src/riden_config/riden_config.cpp manages dongle settings such as timezone and UART configuration; timezone data is in src/riden_config/timezones.h. Runtime infrastructure includes ESP Wi-Fi provisioning via WiFiManager, IPv4 LAN connectivity, mDNS service advertising, NTP synchronization against pool.ntp.org, and OTA firmware delivery through the HTTP interface. The resulting clock/time configuration is propagated to the PSU through the Modbus access layer.