On Thursday 02 December 2010 12:51:16 David Kuehling wrote: > if you are interested in this kind of extremely compact FPGA CPUs, you > might like this one, too: > > http://opensource.zylin.com/zpu.htm > > Pretty professional, even a GCC toolchain is available, and > BSD-licensed. This also uses a zero-operand architecture (i.e. operands > on hardware-stack), so one might call it a "forth" cpu.
Tried it for the Milkymist USB controller and quickly dropped it (designing using my own AVR clone to replace it). It basically looks like a contest winner for the slowest and most inefficient CPU you can promote with a straight face. As it turned out, that piece of crap takes more than 256 clock cycles per byte for a rather simple buffer copy code... It failed to feed the data to my USB UART operating at 1.5Mbps while the CPU itself was running at 48MHz. That's ludicrous. By the way, why is it always poor or stupid designs that make hackaday and all the buzz? I've read countless times about this J1, Plasma, another crappy AVR clone and ZPU. S. _______________________________________________ Qi Hardware Discussion List Mail to list (members only): [email protected] Subscribe or Unsubscribe: http://lists.en.qi-hardware.com/mailman/listinfo/discussion
