RPI | RPIC | DPR | QPR | FTC | SRO4 | SRI4 | PTP | RSE
The vital link between the PC and the layout. This module receives commands from the PC and distributes the data to and from the other modules in the 'Stack'. Two versions are available: for Single Panel applications using a standard RS232 interface (COM port) and for Multiple Panel applications using an RS485 multi-drop interface. For RS485 systems, the RSB adaptor is available which simply plugs into a conventional RS232 COM port. and controls the operation of the RS485 side of things automatically, according to the RPC protocol. Recent development work on the RPI module has resulted in adding DCC Packet generation, either under PC control or manually using Handsets. This new capability currently extends to:
The new design of Interface module using Microchip PIC devices. This module receives commands from the PC and distributes the data to and from the other modules in the 'Stack', just like the original RPI. Four new versions are available: for Single Panel applications using a standard RS232 interface (COM port), Multiple Panel applications using an RS485 multi-drop interface, USB 1.1 low speed for Single Panel applications, and USB 1.1 low speed with RS485 Slave Extension Bus. The first two effectively replace the original RPI types. For RS485 systems, the RSB adaptor is available which simply plugs into a conventional RS232 COM port. and controls the operation of the RS485 side of things automatically, according to the RPC protocol. The PIC based modules do not support DCC as yet. The version shown in the picture is the RPICUSB+, which provides layout operation with an RS485 extension bus, in addition to its own Stack controls. The spare holes in the PCB accommodate the devices used on the alternative versions. As the same PCB is used for all versions, you simply fit the devices required for the chosen type.
Eight BT47 Style DPDT relays individually controlled via the RPI, with the coil drive connections brought out to a separate connector to allow the drive signals to be used externally, particularly intended for point operation, where the associated relay contacts can be used for frog switching on live frog track systems. Additionally, this connector allows external manual switches to operate the relays if desired. Note that the relays themselves are not included in the kit, leaving the choice of coil voltage to the User. +5V, +12V and +24V operating relays are suitable.
Eight 4PDT relays individually controlled via the RPI, with the coil drive connections brought out to a separate connector to allow the drive signals to be used externally. Basically the same as the DPR Module, but intended for more complex switching requirements particularly around complicated live frog pointwork. Currently supplied with +24V operating relays.
Eight Continuous Train-on-Track Detectors, using current flow in the live (or switched) rail as the detection method. Live rail detection allows standard Common Return layout wiring principles to be used. Each detector circuit is simply wired in series with the existing section feed. Bias supplies are used to allow the detection to function whether the train is in motion (in either direction) or stationary. Detected outputs are fed back to the PC via the RPI under software control. It is also possible to arrange for local indications using LEDs (not supplied). The FTC module is compatible with DCC systems, and because track power is always available in such systems, one less bias supply is needed.
Thirty-two Open Collector outputs, arranged as four groups of eight. Each output is individually controlled via the RPI, and can sink up to 500mA each, within the power dissipation limits of the output devices. A ground (0V) connection is provided in each group, as well as an option to use either the in-built Back-EMF protection diodes, or the logic supply rail (+5V). Typical uses for this module include Signal driving (such as with the SD4), Panel LED driving etc.
Thirty-two Logic level inputs, arranged as four groups of eight. Each input is individually readable via the RPI, and is TTL/5V CMOS Compatible. Other input levels can easily be accommodated by using external resistor networks if desired. Ground (0V) and Logic supply (+5V) connections are provided in each group. Typical uses for this module include Point Correspondence feedback and Switch inputs.
Used as a "Master-Slave" pair, PTP Modules provide two-way manual control of up to 960 layout functions via a single Screened Twisted Pair cable at distances up to 4000ft (1200m). Layout data is transferred automatically more than twenty times per second, giving the "feel" of continuous operation. Standard RPC Modules plug into the PTP Module at each end of the link, in the same fashion as with an RPI, which the PTP replaces at the "head" of the module stack.
Used as a "Master-Slave" pair, the two RSE Modules (RSM - Master and RSS - Slave) provide the means to split a module stack. This allows modules to be located remotely from the main stack with its interface module (RPI or PTP) controlling both parts. The RSE modules simply buffer the shift register control and data signals present on the stacking connector, and operation is transparent to the user. The RSM (shown left) plugs into the end of the main stack, and the RSS (shown right) forms the "head" of the extended stack. Connection is by standard off-the-shelf 4 pair Cat 5 network cables using RJ45 connectors.
A self-contained Capacitor Discharge twin-solenoid motor driver, controlled by a single low current wire. This wire is simply connected to Ground (0V) for one direction, and left Open-circuit for the opposite direction. Jumpers links are provided to allow the default 'Normal' and ''Reverse' directions to be selected.
A variant of the PMD1, which includes a Double Pole Double Throw (DPDT) relay for general purpose switching in the vicinity of the point. under control. Such uses might include frog polarity switching for live frog points. The relay fitted can switch and carry currents up to 2A. Another feature of this design are the unpluggable Terminal Blocks, which are used for all connections, allowing quick and easy maintenance. All other featiures are identical to the PMD1.
For use with Multiple Aspect Colour Light Signals using LEDs. This design requires that the LEDs on the Signal itself are arranged as two back-to-back pairs, with a common connection to both pairs. Thus three wires are all that is needed on the Signal to generate all four aspect combinations. The inputs to the SD4 are two bit binary coded derived from, typically, an SRO4 module. Additional facilities are provided for Junction Indicators or 'Feathers'.
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