3 ms·
Author here if anyone has questions...
by kens 9mo ago
Author here if anyone has questions...
- farseer 9mo agoIs there 8087 IP available in verilog etc?
- kens 9mo agoAs far as I know, you can't get the 8087 itself as an IP block. You can get generic IEEE-754 floating-point as an IP block, e.g. from AMD: https://www.amd.com/en/products/adaptive-socs-and-fpgas/intellectual-property/floating_pt.html https://www.amd.com/en/products/adaptive-socs-and-fpgas/inte...
- pwdisswordfishy 9mo agoIPv6 has seriously gone too far.
- hnthrowaway0315 9mo agoHi kens, thanks for the knowledge sharing all these years. Can you please confirm this one? From Wikipedia, it says that 8087 uses CORDIC algorithm. Does that mean that it's the same (but different speed) as what I'd implement the functions in software, except in microcode (which has more granularity than usual assembly code)? I found it a bit surprising that as a 45-year old chip, there is no public information of its microcode. I guess hardware is indeed much more secret than software.
- kens 9mo agoYes, the 8087 uses CORDIC. I extracted the constants from the 8087's internal constant ROM and they are arctangent and log values for the CORDIC algorithm. You can implement the same functions in software, which is what floating-point emulation libraries did back then. There's almost no public information on the 8087 microcode, but I'm working on that :-)
- hnthrowaway0315 9mo agoThanks Ken, appreciate the work!
- dapperdrake 9mo agoThank you for the deep dive.
- mschaef 9mo agoThank you. As always.