Outstanding Bill! And it will be programmed in Assembly! Are you using some tricks to improve the reliability of "reading" AC line? Either HW or SW. In Europe AC time is currently running 32 seconds late since the beginning of the year. It will catch up, as it did in 2018 when the grid had "lost" 300 seconds in 3 months. Every time I think my IN-14 clock has troubles with AC pulses, but in fact it's the grid running noticeably fast or slow.
Paolo On Wed, Jun 19, 2019 at 1:43 AM Bill Stanley <[email protected]> wrote: > > > I promised to post some details on my current Nixie nightmare. I present: > > > The BRS Clock > > The current version of the clock is in 2 (or more) PCBs. This was done to > allow changes to the display type by only either changing the display board > or the display cluster boards. The board can be used with Nixie tubes (10 > cathode or 14 cathode “British Flag” types), LEDs, possibly VF or other. > > > The CPU board: > > A pair of 16 pin headers on top of the CPU board connects it to the > display. The CPU supplies 12V, 5V and 170V with the 170 able to be margined > by the CPU. I2C connects “things” on the display to the CPU. The time data > is sent in a serial format (clock+data) along with a transfer strobe to > write the data to the tubes. For Nixie displays, the HV5812PJ-G chip does > direct drive to the cathodes, there is no multiplexing. Additional signals > include a room light sensor an 11 pins defined for control like decimal > points, symbols and “pimp lights”. > > > The CPU is currently a Silicon Labs C8051F360 > > > Time base. There a 4 possible time base sources for the clock. In > increasing accuracy order: > > The CPU time base: This is the worst but with some work can be trimmed up > somewhat. If this is the only time base, the clock will lose time in a > power failure. > > AC line clock: The primary power source is 12V. It can be AC or DC. If the > power source is 12V AC, the line frequency is sampled (50 or 60Hz detected) > and used to run the clock. The AC line has good long term stability, much > better than the CPU clock. As with the CPU clock, a power failure will > reset the clock date/time. > > DS3231S: This Maxim chip along with a coin cell has very good accuracy and > will remember the date/time during a power failure. > > GPS: An optional Trimble Lassen GPS receiver can be plugged onto the CPU > board. It provides a very accurate 1PPS signal and UTC date/time for the > highest accuracy. Other GPS receivers that support the NMEA sentence > structure and a 1 PPS signal could also be used. The GPS has a battery > backup to allow faster cold starts. > > > 6 pushbuttons (plus reset) allow user setting of date, time and setup > parameters. The parameters are saved in EEPROM so are available after a > power-down. 1 button sets/unsets DST so the twice a year change is simple. > > > There are a number of connectors to plug in various external devices. They > are > > Indoor temperature/humidity: A small sensor will allow the display the > indoor temperature and humidity every 5 minutes. > > Outdoor temperature: A different small sensor will display the outdoor > temperature at the same time as the indoor, if connected. > > PIR/room light: A Passive IR motion sensor and room light level sensor > will allow shutdown in darkness when no-one is around. The room light > sensor can adjust the brightness of the pimp lights automatically. > > MP3 player: A simple MP3 player is connected to play different sounds at > different times. The current code plays the Westminster Chimes on the > quarter hour and the hour count at the top of the hour. Many other things > could be done. > > Meter DAC: My friend wanted a “Steam Punk” look to the clock so we > incorporated 3 D/A converters (12 bit accuracy) driven at a 1/10 second > update rate with the H/M/S. He will use these to drive vintage large analog > meters so the time will be read as analog. > > Stopwatch: Another request was for a work clock that displayed a running > stopwatch every 5 minutes. Three control switches are provided to > start/stop/reset the stopwatch. > > > Displays > > The displays are mounted on a daughter card plugged into the CPU. This > allowed me to only modify the display to run with a number of different > display types. The following information is for Nixi display tubes. > > > Tubes: Designed using the ‘QTC’ concept from pvelectronics in UK. This > mounts the tube (solder or socket) on a small PCB that plugs into the > display board with a 12 pin 0.1” connector. I have created adaptors for > about 8 or so different tubes. New tubes are quick to create. The original > used IN-14 + IN-19 tubes > > > Bottom lights: These lights shine thru the base of the tube thru a hole in > the QTC board. I call these “pimp lights” and come in 2 flavors; a standard > single RGB LED that cycles automatically thru multiple colors and a > dedicated WS2812B RGB LED that is individually programmed with 256 levels > of each color. The WS2812B is currently programmed to cycle thru colors > once a minute (seconds), once an hour (minutes) and once a day (hours). For > example, on the seconds, the color starts at 100% red at 00. The red drops > and the green rises and a 1/10 second rate until at 20, the light is full > green. Green then drops and blue comes up so that at 40, it is 100% blue. > Blue then drops and red comes up so that at 00, we are back to 100% red. > Pimp lights are lead zero blanked with the tubes, depending on the selected > lead zero blanking (LZB) mode. > > > Symbols: If a compatible symbol tube exists, it is installed to the right > of hours, minutes and seconds. When the time is displayed, the symbols > display H/M/S. When displaying temperature, they display F/% (temp and > humidity) in other modes they are blanked. > > > Display boards: there are currently 3 display boards; small, large and > cluster. > > The small display board was designed for the IN-14 digit/IN-19 symbol > tubes. With the QTC changes I have operated other tubes such as the B-5750. > > The large display board was for bigger tubes like the Z560M digits/IN-15 > symbols. It could also work for IN-12 digits. > > The cluster display was created to allow different sizes of displays to be > quickly created. The concept is that a hub board is plugged into the CPU. > The hub then splits off to 3 20 pin ribbon cables, 1 each for H/M/S. > Plugged into the far end of the cable is a display clusted board that holds > the driver and QTC sockets for 3 displays. The common hub exists and a > cluster has been designed for the Z560M digits/IN-15 symbols. The cables > ease the mounting requirements for larger displays. It should also work > well for the upside-down HP displays > > > Open Source: I am not making this a business. I usually fab more boards > that I need and some down-level stuff exist. I am willing to share what I > have and know so I will supply the schematics (OrCad/PDF), PCB layout > (allegro/gerbers) and code (8051 assembly language). If you need some other > display adapted (Panaplex, LED etc) let me know. If it interests me > (semi-retired) I can help or make suggestions. All of these boards are > surface mount based. The smallest part is 0603 so not super small. If > needed, I could solder tough parts that require a fine tim or hot air mount > the 2 parts that need it. > > If you have any questions, want documentation or availability, let me > know. I am a master of questionable answers (or was that answerable > questions?). Always glad to get a question starting with “could you…..” or > have you ever…. > > -Other Bill- > > > > -- > You received this message because you are subscribed to the Google Groups > "neonixie-l" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > To view this discussion on the web, visit > https://groups.google.com/d/msgid/neonixie-l/0215e2e7-a5d1-4f53-9628-4fb196aeecc4%40googlegroups.com > <https://groups.google.com/d/msgid/neonixie-l/0215e2e7-a5d1-4f53-9628-4fb196aeecc4%40googlegroups.com?utm_medium=email&utm_source=footer> > . > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send an email to [email protected]. 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