PDA

View Full Version : WTB Altair Paper Tapes


TomL_12953
05-19-2008, 05:51 PM
Looking for any Altair paper tapes (or copies). Looking for Assembler, monitor and especially 8K and Extended BASIC. I recently got an ASR-33 and can't wait to try it out with the Altair replica when I get it.

Cappellanus
05-20-2008, 02:39 AM
Do binary images exist for any programs? I've seen a few original Altair tapes go for auction, but no web site I've seen has the actual binary images. If I could see the data, I have a whole ton of paper tape rolls (high-quality mylar, black-paper, and yellow paper) as well a high-speed late model paper tape punch, so I could print the tapes easilly.

Has anyone found true "paper tape images" for programs anyplace? Most of the programs, like BASIC, seem to just be binary memory dumps. Maybe I'm looking in the wrong places.

TomL_12953
05-20-2008, 10:50 AM
I believe that the memory images ARE the same as the paper tape images. The paper tape simply has all the bytes of the memory image which are loaded into memory by the bootstrap program that you toggle in. That is unless the original paper tape had its own more extensive boot loader as a preface to the data. If someone knows the format of Altair tapes, please let us know! The software to create the tapes from the bin image is trivial if I know the format. I would gladly produce tapes for anyone who wants them for just the cost of shipping plus a small bit to cover my paper tape cost.

The binary images are here:

http://simh.trailing-edge.com/software.html

The link is the third from the bottom

CP/M and DOS...

click on "updated kit" and you'll get a ZIP file with all the BASICs in it. I'd like to get 4Kbas.bin, 8kbas.bin and exbas.bin converted. That would be great!

I can also make my own tapes (at 110 baud) but I have a question about the parity bit. My ASR-33 uses even parity, as usual. The first byte of exbas.bin is hex F3.
how would the paper tape have that punched? Would the parity hole be punched or not and when it's read back, would the interface throw away that bit?


Tom L