IO4-Turtle
IO4 Tortoise driver with occupancy and point position feedback
Carrier board, DFM, feedback LEDS that don’t pass tortoise current and IO4 Tortoise driver with occupancy and point position feedback
Download IO4-Turtle_array.scr - Eagle SCRipt
Download Untitled 2 -
Download lm1117-Datasheet.pdf - Documentation
Documentation
This is an adaptation of my older PIC-based ExpressPCB Turtle project, which is why the version numbers start at 4…. It has evolved quite a bit, in form factor and functionality as it has been used on my layout.
This board mounts on a Tortoise via a sweat-soldered right angle Molex M-M connector, plugs into an IOB-Turtle or other IO4 compatible port.
The Tortoise provides:
- OS section occupancy (so you don’t throw a turnout out from under a train…),
- Turnout point position feedback (Normal, in transit, Diverging)
- easy frog polarity changes for dealing with wiring mishaps
- easy Normal/Reverse changes for when the Normal route thru a turnout needs to go the other way.
- Tortoise motor debouncing when it reaches the end of travel
- feedback LEDs to show Occupancy (yellow) and commanded position (red/green)
It uses my standard IO4 RJ12/6 wiring interface:
- pin 1: 9-12vDC
- pin 2: !DIVERGING - Turnout Position Feedback - low = Diverging, high = not diverging
- pin 3: !NORMAL - Turnout Position Feedback - low = Normal, high = not normal
- pin 4: !OCCUPIED - Detector Feedback - low = occupied, high = empty
- pin 5: !MOTOR - Motor Control Input - Low = Normal, High = Diverging
- pin 6: GND
It also connects to the local DCC track power feed and to the turnout’s isolated-for-detection-purposes stock and frog rails.
This technical documentation is licensed under the CERN Open Hardware Licence v1.2