A DIN-rail-mounted 16 I/O device designed to operate mostly as a SEXI slave.

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== Version 4.5 ==
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18 June 2026
- Made PA9 an IO_UNUSED pin since it's not using VBUS.
- Changed board type so it would show up as SPLat rather than HMI430
- Lots of SPLatVM updates, including:
   - Modified Modbus Slave code to only get the RAM Mutex when needed and to release it before sending a response so it doesn't interfere with Xwire.
   - Added code to enable the build date and time to be retrieved.
   - Added Random Number Generation
   - Added extra Modbus capabilities
   - Allowance for higher-speed Xwire
   - Allowance for extra 64KB of space for SPLat + NVEM0
   - 16-bit SPLat implementation, including debugging
   - Bug fixes

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== Version 4.4 ==
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25 June 2020
- Simplified SPLat code to single version.

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== Version 4.3 ==
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28 April 2020
- Restored 1806 and 1808 to the same I/O map and Xwire signals.
- Re-built both variants with current system changes, including NVEM3.
- Removed Quadrature initialisation from 1806 variant so analog output 0 could work.

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== Version 4.3 (unreleased) ==
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25 October 2019 (never released, never tagged)
- Work in progress on extended outputs for 1808 version, not working

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== Version 4.2 ==
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16 April 2019
- First pass of 1808 version.

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== Version 4.1 ==
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25Oct2018
- DM16: can now drive outputs 7, 8, 9 as either digital or analogue
- VM: added generic module for driving outputs as either analogue or digital
- VM: suspend and resume were using little endian rather than big endian, never caused a problem, only a train spotter would notice.
- VM: UVtoNV wasn't working right as it was ignoring the "offset", so now modified for use in ARM meaning V must be explicitly set, it won't use NVRecLen to allow for a more flexible instruction.
- VM: added support for OBLCD_HGraph, OBLCD_CursorOff, OBLCD_CursorOn, OBLCD_CursorBlink.  These also work over Xwire, both as master and as slave.

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== Version 4.0 ==
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03Aug2018
- First release