Chuck Guzis wrote: At the moment, I use a high speed stream protocol over USB, via the brilliant fpgalink library by Bruce McClelland ( http://www.makestuff.eu/wordpress/software/fpgalink/ ) to a bit of python code on a PC which takes files and sends them as card column signals to my 2501 reader emulation logic in the fpga. I am mapping all the signals from the 2501 to the adapter circuits in the 1130, timing everything and modeling state as close to a real 2501 as I can determine, so that it appears that the photocells are detecting holes at the right time as the card virtually slides through the emulated transport, but the content of the columns that get turned into lights are stuffed into a FIFO by the link from the PC. However, someone has offered a small card reader that I will be gratefully accepting and utilizing. I plan to map the real reader as the 2501 and use my alternate 1442 reader/punch emulation over the fpgalink channels so that I can both read real cards and read files on the PC as virtual cards. Yes, the 2501 just delivered to the 1130 one bit for each of the 12 card rows, exactly what was punched in that column. The 1130 programmer would convert the Hollerith coded characters into whatever other coding they wanted in their program. Boot mode wired the signals a bit differently to provide a 16 bit result to the 1130 that was usable as initial program load instructions, that is done in the 1130 adapter logic, not in the 2501. Finally, various forms of binary coding were used in the 1130, such as the user program format and a special binary mode used by diagnostic programs, but all of those are just the status of holes in a column sent as 12 bits plus 0000 to form an 1130 word. My python program converts ascii files to Hollerith, as well as delivering binary mode files directly as card hole images. I don't personally know of any fpga emulations of 1620 machines, but there are excellent simulators available. Carl ________________________________ This e-mail message, including any attachments, is for the sole use of the person to whom it has been sent, and may contain information that is confidential or legally protected. If you are not the intended recipient or have received this message in error, you are not authorized to copy, distribute, or otherwise use this message or its attachments. Please notify the sender immediately by return e-mail and permanently delete this message and any attachments. Gartner makes no warranty that this e-mail is error or virus free.