TMWACC

Accessory decoders.

The two decoders can be programed in page- and direct mode from a programing track, and on the main. Ack is implemented, so you can read out the CVs from the decoder.

This is a prototype Tmwacc1 with the power limit circuit omitted for test purpose. Do not do that. Note the two pigibacked ULN chips.

TMWACC1 decoder is a NMRA-DCC compatible decoder, designed to handle four Peco/Roco twin coil turnout motors. It is powered by the DCC track or by a dedicated DCC booster. The outputs can be controled independently, and can have an adjustable ON time or be left ON continuously.
The decoder is set up with a decoder address.
Decoder #1 controls turnout number 1 - 4
decoder #2 controls turnouts 5 - 8 and so on.

The CVs used are as follow:

513 Decoder address LSB
514 Enable output
515 On-time pair 1
516 On-time pair 2
517 On-time pair 3
518 On-time pair 4
519 Version (Read only)
520 Manufacturer ID(Read only)
521 Decoder address MSB
541 Configuration (Read only)

The micro code is identical to the code originally written by Dean Probst to be used in his locomotive decoders, modified to controll the MERG accessory decoder, by Mike Bolton .

tmwacc1.zip is a file containing the schematics, source code, hex file, manual and an etch pattern. (One resistor value corrected.)

The TMWACC2 decoder is a NMRA-DCC compatible decoder, designed to handle four Tortoise slow motion turnout motors. The point blades travel slowly and soundlessly when driven by this decoder. The power can be left continuously ON, or can be sent to the motors for an adjustable time range.
It is powered by the DCC track or by a dedicated DCC booster. The outputs can NOT be controled independently, but are linked together in pairs.
The decoder is set up with a decoder address.
Decoder #1 controls turnout number 1 - 4
Decoder #2 controls turnouts 5 - 8 and so on.

The micro code is originally written by Dean Probst to be used in his locomotive decoders, modified to controll the MERG accessory decoder, by Mike Bolton, and now modified by me to fit my hardware.

The CVs used are as follow:

513 Decoder address LSB
514 Enable output
515 On-time pair 1
516 On-time pair 2
517 On-time pair 3
518 On-time pair 4
519 Version (Read only)
520 Manufacturer ID(Read only)
521 Decoder address MSB
541 Configuration (Read only)

tmwacc2.zip is a file containing the schematics, source code, hex file, manual and an etch pattern.

A device to be used for loading the PIC processors with the hex file can be found here.

Programming tools

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