[Simh] Ferranti Pegasus Simulator

[Dave Wade]

Whilst its not a SIMH simulator, I hope you can help. I want to write an
emulator for the Pegasus. The Ferranti Pegasus was (there are none operating
at present) a strange beast with two 18-bit instructions per 39-bit word.
Generally, it does 39-bit twos complement arithmetic. The multiply results
in a 77-bit result which I have no problems implementing.
 
Where I am struggling is with the divide. I need to be able to divide a
77-bit number by a 39-bit number and get a 39 bit quotient and a 39 bit
remainder. As the compiler I am using only does 64-bit numbers this is
proving challenging. Any one got a good article on how to do this?
 
Dave Wade
G4UGM
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.trailing-edge.com/pipermail/simh/attachments/20160611/d0393f5e/attachment-0001.html>