photo of USB2LPT2

Keywords: USB, LPT, parallel, parallel port, printer port, converter, adaptor

USB2LPT — overview

USB2LPT, List of successfully tested programs

This list should grow with appropriate user feedback…

Attention: Using USB2LPT with programming devices may lead to wrong or bad programmed chips! The reason is lengthening of the programming pulse due to longer parallel port access emulation time. The result depends on
  • whether the PC software or the programming device creates the programming pulse
  • whether the chip requires timely exact pulses or not. In general, ISP chips (newer micro controllers, or JTAG interfaces), serial EEPROMs, and flash memories are excluded.
If the length of programming pulse is important (e.g. for correct programming in mass production), USB2LPT should not be used. Furthermore, programming software should not be installed onto too fast computers. Depending on software quality, this may lead to too short programming pulses.
Attention 2: Although using USB2LPT with programming devices is obvious, it is generally not recommended. Programing times are much too long to get ready. At the top I measured that the GALEP software needs some minutes(!) for programming the smallest PIC (12F508).
PCMCIA parallel adapters do not have this disadvantage. However, most ExpressCard adapter won't work.
There is also a list of unsuccessfully tested applications: