Delete comment from: Ken Shirriff's blog
Great article, Ken -- we at TechWorks! had anticipated assigning a computer science intern to the task of figuring out the magic of the program and the frequency cards, but you beat us to it! As usual, your explanation of a complex thing is simple and clear, removing the veil from our eyes in just a few paragraphs. A few questions, though:
-- is there some provision required for aligning the print chain to its home position prior to printing so that the characters always print in the proper sequence?
-- did you use some modification of your print chain / hammer sequence demo to easily figure out the frequency line data, or was it just brute force on your part? If the former, is that code available for use?
-- as you know, we have a working 1403-N1 printer at TechWorks! that runs at almost twice the speed of the CHM models (1100 LPM). We'd like to adapt the frequency cards to play on our printer, so any help you can offer on that front would be appreciated. Also note that our printer is not attached to a 1401 -- it essentially prints from a text file generated on a PC -- so "songs" will have to be constructed by assembling frequency print lines into the text file with rests implemented by blank lines, I think.
Jan 21, 2020, 10:10:19 PM
Posted to Risky line printer music on a vintage IBM mainframe