On 22.05.2011 11:34, Bernhard Walle wrote: > If the parport is used as low-level I/O device (like done for simple > logic analyzers or programmer devices for microcontrollers), the host > changes the direction of the parallel port as input and reads the data bits. > > Reading has already been implemented, but the direction change was not > forwarded to the ppdev driver on Linux. So what the guest read was not > the state of the hardware but the last value written to the port. > > This patch implements changing the direction. The patch has been tested > on Linux host (Arch Linux) with a Linux guest (openSUSE 11.4) with a > simple parport.c file (attached) and with a Windows XP guest (Windows XP > with all patches) with tfla-01.berlios.de and giveio.sys.
Just for the record: the functionality is included in the VirtualBox parallel port code since December 2011 (will become part of version 4.2). The contribution served as inspiration from what I can tell by looking at the actual code in the VirtualBox tree. Thank you very much for the contribution. It did help making progress, even though the patch as such wasn't actually used this time. Klaus _______________________________________________ vbox-dev mailing list [email protected] https://www.virtualbox.org/mailman/listinfo/vbox-dev
