Propeller Schematics

The interfacing hardware has been changed somewhat with the moving from Basic Stamps to the Propeller chip. The new circuits take advantage of the higher performance of the Propeller chip and some of the functions have been moved to software. The turnout drivers are improved to minimize external parts and provide an additional measure of protection to the switch machine coils. The DCC only block detectors use a different transformer isolation circuit to minimize parts and eliminate the need for the high current diodes. The inputs and outputs are interfaced using serial/parallel shift registers. This is one of the areas where the higher performance of the Propeller chip makes this easier to accomplish. The power supply circuit now includes a 3.3 volt output but is essentially unchanged from the Basic Stamp version.

The Propeller P8X32A-Q44 ProtoBoard (Q1 2007 availablity) will be used. This board is expected to contain the following components.

Use the following links to view the circuits on each schematic sheet.

Propeller Circuits
Solenoid Switch Machine Driver Circuits
Input Sensor Circuits
LED Driver Circuits
Keypad and Button Interface Circuits
Power Supply Circuits

Color Bar

Planning and Construction:   Design Goals   Track Plan   Photos   Scenery Base
Basic Stamp Control Electronics:   Main line   Yard   Grade Crossing   Block Signal   Turntable
Circuit Description:   Main line   Yard   Grade Crossing   Block Signal   Block Detector   Turntable   Power Supply   Schematics
Photos and Video clips:   Photo 1   Photo 2   Photo 3   Photo 4   Photo 5   Photo 6   Video Clips   Ride The D&B
Propeller Control Electronics:   Overview   Flow Charts   Program Code   Schematics   Photos
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Copyright © 2006 Don Buczynski
San Diego, California