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A LocoIO board is a DIY stationary interface to LocoNet for inputs (fascia pushbuttons,
turnout feedback or occupancy sensors) and outputs (fascia indicator LEDs, signal LED's,
turnout motors etc.). The original LocoIO design by John Jabour was further
developed by Hans Deloof from Belgium.
A typical board contains 16 signal pins, also called channels or ports. Each port can be individually programmed as an input or an output, and to perform a number of different things (depending on the module's hardware and firmware (PIC) version:
Since LocoIO rev 1.49
See the Cheat Sheet included in the DecoderPro LocoIO Programmer for further details.
The ports are configured via LocoNet messages, but the DecoderPro Programming interface takes care of many technical details. Documentation is included below and in the decoder definition file.
The Public_Domain_HDL_LocoIO Decoder Definition in the "Public Domain and DIY" category supports set-up of a wide range of LocoIO devices up to LocoIO/LocoBooster/LocoRCD/LocoServo rev 1.54 hardware since 2020.
To use the current LocoIO Programmer follow these steps:
The following entry is only shown as reference for JMRI versions before 3.0.
You can still use it for the original boards, but consider switching over to configuring your LocoIO boards with the current programmer, documented above.
Version 2 was written by John Plocher for JMRI release 1.8 and only dealt with SV1 & SV2 (address/subaddress) and SV3-SV50 (primary Mode, Value1 and Value2 for ports 1-16). In particular, it did not handle SV0 (board level configuration), SV51-SV98 (alternate Opcodes) or SV101-124 (servo config).
The first LocoIO programmer was part of JMRI 1.x. It provided a table-based interface for configuring John Jabour's LocoIO board, a powerful component for building CTC boards and control panels. (More information on the board is available at http://www.locobuffer.com/LocoIO/LocoIO.htm)
The LocoIO programmer v1 used a table to represent the configuration of each channel.
The "Action" column is used to select how the channel/port behaves. Click in a cell to be given a menu of available choices. Currently, the choices are:
Generate a OPC_SW_REQ to close/throw a turnout when a toggle switch changes state. When the input goes high, a "close" command is sent; when the input goes low, a "throw" command is sent. The channel configuration value is 0x0F.
Generate a OPC_SW_REQ LocoNet message when the input goes low. This is intended for use with a momentary pushbutton. The command sent will alternate the position of the addressed turnout or signal; if "close" was last sent, a "throw" will be sent now and vice-versa. The channel configuration value is 0x2F.
Generate a OPC_SW_REQ LocoNet message when the input goes high. This is intended for use with a momentary pushbutton. The command sent will alternate the position of the addressed turnout or signal; if "close" was last sent, a "throw" will be sent now and vice-versa. The channel configuration value is 0x6F.
Drive an output from OPC_INPUT_REP input status messages on the LocoNet. The output goes high when an "input high" message is received, and goes low when an "input low" message is received. These messages are also used for block occupancy status; the output will go high when the block is occupied, and low when its empty. The channel configuration value is 0XC0.
Drive an output on the LocoIO board from received OPC_SW_REQ commands. The channel configuration value is 0x80. This adjusts the address field to look for a command that sets the turnout "closed".
Drive an output on the LocoIO board from received OPC_SW_REQ commands. The channel configuration value is 0x80. This adjusts the address field to look for a command that sets the turnout "thrown".
The "Hex Value1,Value2" column sets the address that the LocoIO board will use for LocoNet communications. This contains a hexadecimal representation of the two configuration values described in John Jabour's LocoIO programming guide. You generally won't need to figure out these addresses, as thebuttons will find them for you.
Thebutton reads from the LocoIO board via the LocoNet and shows the current configuration for that pin. The button stores the current settings to the LocoIO board.
Thebutton provides an easier way to find a needed LocoNet address. Configure the input and output for a particular pin, then press the button. The address in the next LocoNet message of the right type will be put in the address column.
For example, if you have a channel set to act when a "Turnout closed status message" is received, press thebutton and use your throttle to command the correct turnout Closed.
As another example, if the channel is configured to send a "Send throw turnout command", press thebutton and use your throttle to command the correct turnout Thrown.
At the bottom of the table are some general controls. The LocoIO address field sets the address of the board being programmed. LocoIO processors are sent with an address of 1051 programmed; see below for how to change that. Address "0" is a global address which any LocoIO board will respond to; make sure you have only one connected when you use that!
Thebutton will use the global address to configure a specific address into a LocoIO board. Again, make sure you have only one connected.
Theand buttons read or write all of the channels, and are just a convenience.
Status messages during capture/read/write are displayed at the bottom of the window. If no response is heard from the LocoIO unit, the operation will be retried until it succeeds or until you close the window.