| ??? 11/26/07 06:32 Read: times |
#147400 - tristates in FPGAs Responding to: ???'s previous message |
Yes, internal TBUFs have been eliminated from the newer Xilinx FPGA families.
But don't fret: a) code written to infer a TBUF will be synthesized to proper muxes. Clever, eh? b) Those long-line tristates, while mighty convenient, were actually slower than most muxes. Only when you got into stuff like 16:1 muxes was there a timing benefit. Of course tristate control logic is simpler than simple tristate enables but a 16:1 mux required 16 enables instead of four. -a |
| Topic | Author | Date |
| Tri-state busses in FPGAs | 01/01/70 00:00 | |
| Tristate Buffers (TBUFs) have been phased out | 01/01/70 00:00 | |
| Thank you | 01/01/70 00:00 | |
| Closing the loop | 01/01/70 00:00 | |
| siumulate? | 01/01/70 00:00 | |
| I didn't simulate it (yet) | 01/01/70 00:00 | |
| hmmm | 01/01/70 00:00 | |
| So ... what about a BIG multi-party bus? | 01/01/70 00:00 | |
| delay | 01/01/70 00:00 | |
| nevertheless ... | 01/01/70 00:00 | |
| re: nevertheless | 01/01/70 00:00 | |
| What disappoints me is the advertising vs reality | 01/01/70 00:00 | |
| advertising | 01/01/70 00:00 | |
| advertising, badvertising ... lies! | 01/01/70 00:00 | |
| oy | 01/01/70 00:00 | |
If only one could rely on them ... | 01/01/70 00:00 | |
| largely, it's because it's not an option | 01/01/70 00:00 | |
| Zackly | 01/01/70 00:00 | |
| If you have internal tristate resources ... | 01/01/70 00:00 | |
| I have new worries now | 01/01/70 00:00 | |
| tristates in FPGAs | 01/01/70 00:00 |



