McScope

This page is about a reference DIY microscpoe control system similar to those used by John McMaster. Its intended to be a good starting place for what options might be for adding automated image capture to a microscope.

Above: high level sample architecture. In this example one axis uses an MDrive17 and a second axis uses a generic stepper motor without integrated driver. However, in a real system you probably want X and Y to use the same motor/drive

Useful links:

• https://github.com/SiliconAnalysis/pyuscope
• https://github.com/SiliconAnalysis/bbb-scope/blob/master/b3index_r1/b3index_r1/b3index_r1.pdf
• https://microwiki.org/media/scopetek/0001-scopetek-directly-control-RGB-gain.patch
• https://microwiki.org/wiki/index.php/Stepper_Motor
• https://www.machinekit.io
• https://beagleboard.org/black

Terminology:

• Indexer: a device that generates step/direction pulses
• Drive: power electronics for (stepper) motor
• Beaglebone Black (BBB): embedded board with lots of accurate timing I/O
• Machinekit: a CNC controller (indexer) distribution for BBB. Based on LinuxCNC
• BBB Indexer (B3I) cape (PCB): allows BBB I/O to adapt to current/voltage requirements of typical drive photodiodes with convenient connections
• BBB Indexer (B3I) system: b3i PCB + BBB assembly

Reference system, focusing on critical components:

• Microscope
  • AmScope MU800 camera
  • MDrive17 stepper motors on XY stage
• b3i system
  • BBB
  • Machinekit
  • B3I cape
• T61p laptop
  • Ubuntu 16.04LTS
  • pyuscope (microscope control software)
  • touptek.ko modified for direct RGB control

Reference workflow:

• Connect BBB over USB to host laptop
• Host laptop: static config IP to 192.168.7.1
• SSH -X from T61p to BBB (192.168.7.2)
  • Launch LinuxCNC software over X
  • Launch server.py RPC client (TODO: bring back automatic launch)
  • Use LinuxCNC GUI for all setup movement, not pyuscope
• Optional: white balance camera using cal.py. Write values to microscope.json
• Start pyuscope software
• Select current objective (ie 20x)
• Use LinuxCNC GUI to navigate around stage and make adjustments to level out
  • TODO: add link / suggestions how to do this
• Use LinuxCNC GUI to navigate to upper left corner of die and in pyuscope hit "set upper left"
• Use LinuxCNC GUI to navigate to lower right corner of die and pyuscope hit "set lower right"

Misc notes:

• b3i default configuration is to power I/O buffers from "SYS_5V", which means external power is required. The easiest way to do this is to supply 5V to the barrel jack using a second USB to barrel jack cable