Hi You need the FPGA to do the timing. A CPU / MCU is not fast enough or deterministic enough to do that. By today’s standards, that’s a small FPGA.
The HP guys did not like to do assembly code if they could avoid it. The “lots of CPU” (for the day) let them run things like Forth. Again, these days that CPU is MCU sized. The next layer to all this is that they did a fairly fancy approach to the disciplining process. With SA enabled on GPS, they had to do more than you would have to do today. That more involved filtering (and hardware) is part of what makes them a pretty good box, even today. Bob > On Dec 4, 2014, at 3:03 PM, Doug Ronald <[email protected]> wrote: > > I have sort of a dumb question about the Lucent KS-24361 RFTGs. Why do you > suppose there is so much compute power in these units? They have the Xilinx > FPGA, and the 68000 CPU just to discipline a 5 MHz oscillator? There must be > more going on with these devices than meets my eyes. > > Thanks anyone, > -Doug W6DSR > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
