Having done a pair of large LED displays, the next imp project I want to tackle is replacing the PIC on my Nixie Clock.
All the PIC is doing is keeping time and driving a pair of HV5622 chips: 32-bit shift registers with open-drain outputs.
So the hardware interface is pretty straightforward, but I’m wondering about time(). I know that I’ll need to run my own timers for anything I want to have happen on a sub-second scale, but it’s not clear to me when the RTC in the imp gets set, and how often it’s updated/corrected.
Being the sort of person who has a nixie clock, I’d like it to be fairly accurate, something in the 10’s of ms range.
Is the RTC in that range, or do I need to do more work on my own to get a good timebase?
No need for an NTP client. Once you have then lose your Wifi connection, the Imp has absolute time within 1ms/hour drift. The code is simple if you’re interested. You can resync as often as you like with a connection. Does shallow sleep keep millis() running? I guess deep sleep does not?