1 What is riverSpider?

riverSpider is a tool that allows effective debugging using the TTP tool chain. It consists of a BASH (Borne-again shell) script that makes use of several typical Unix/Linux tools.

Because riverSpider started as a Linux tool to help the instructor improve programming efficiency, it was never designed to work on Windows. As more students who use Windows exclusively want to benefit from this tool, the instructor looked into ways to get riverSpider to work on Windows. There is already a solution using PowerShell, but that still has dependency on the installation of PowerShell 7, and the script is significantly different from the BASH version.

Note that riverSpider includes logisim310.jar. As such, riverSpider is also useful for projects that do not involve the use of TTP and the assembler.

2 What is Cygwin?

Cygwin consists of a DLL (dynamically linked library) that provides an emulation layer so that programs designed for a Unix/Linux environment can cross compile and run on Windows. Cygwin also includes a typical set of command line tools that exist in Unix/Linux systems.

Typically, Cygwin requires an installation that is not designed to be “portable.” This means the installation requires administrative permission, and it is not easy to transport the installation from one computer to another. A portable Cygwin installation, however, allows the installation (a folder) to be put on a thumbdrive or any portable medium, and have the tool to run on most Windows computers.

The main advantage of using Cygwin is that Unix/Linux commands will work in Windows without installing a Linux VM.

3 Getting the Cygwin-based riverSpider to work

• Download cygRiverSpider.7z. This file has a size of about 330 MB.
• Use 7-zip to extract the files.
  • You can extract to a folder on a thumb drive so that the “installation” is portable.
  • The extraction can take very long using slower thumb drives, be patient!
  • Even in a virtualized environment, extraction to a hard drive takes 6 minutes.
• The “home folder” is located at cygRiverSpider/cygwin/cygwin/home/root, assuming cygRiverSpider is where the ZIP file is extracted to.
  • You can create additional folders in the “home folder” for your projects.
• Once extracted, use cygwin-portable.cmd to start a Cygwin shell.
• It is best to download files to the home folder, or subfolders there of.
  • You can change your browser to always ask the destination when you download files.
• If you are writing programs for TTP:
  • In the Cygwin shell, use cd riverSpider to change the working directory to riverSpider.
  • Use notepad READM.md to read the markDown read-me file.
  • after setting up all the files as described in the read-me file (this also involves some work in the corresponding Google Sheets document), use ./submit.sh to submit a TTPASM file.
• For general use:
  • A shell script logisim.sh is created to make it easier to launch Logisim. You can supply additional arguments and switches.