Quick hack commandline tools to interact with Altera FPGA Virtual JTAG interfaces, using the USB Blaster device (as integrated on Terasic dev boards, etc). Not terribly fancy or optimized but only depends on libusb-1.0 Currently does not support multiple devices on the chain. jtag.c - provides simple jtag interface jtag-virtual.c - provides simple virtual jtag interface jload.c - example of using the virtual jtag interface for a downloader interface with a CTRL/ADDR/DATA register set. CTRL[0] asserts reset, writes to DATA store to [ADDR] and auto-increment ADRR. jinfo.c - dumps idcode and virtual jtag hub and device info table Why? Scripting the Altera quartus_stp tool in TCL was driving me nuts.