Nixie Display Interfacing to MINI-MAX/51-C2

The MINI-MAX/51-C2 can drive Nixie tubes via 74141 Nixie BCD Decoder Driver  TTL IC's. MINI-MAX/51-C2 has 32 I/O port pins:

Port Pins Description
P3.0, P3.1 Reserved for RS232 Serial Port
P1.5 Reserved for slave processor
P1.6,P1.7 Reserved for I2C Bus
P3.2, P3.3, P3.4, P3.5, P3.6, P3.7 6 port pins for Nixie interfacing
P2 8 port pins for Nixie interfacing
P0 8 port pins for Nixie interfacing
P1.0, P1.1, P1.2, P1.3 4 port pins for Nixie interfacing

Each 74141 BCD Decoder/Driver uses 4 port pins.

Therefore, each MINI-MAX/51-C2 can support up to 6 digit displays for clocks that need to display time in an Hours:Minutes:Seconds format. In addition to displaying time, the MINI-MAX/51-C2 can display virtually any value on the Nixie tube using available option boards. For example, the MINI-MAX/51-C2 can display analog voltages on the Nixies using its on board 5 channel analog inputs.

Example wiring diagram

The MINI-MAX/51-C2, through its PC based interface, allows the user to create BASIC or C programs that allow maximum flexibility in presenting information on the Nixie tubes. This eliminates the need for hardwiring the displays for a dedicated function. To switch from a clock to a temperature display is as easy a writing a new short program on the PC and downloading it to the controller. No wiring changes necessary. In addition, with the available Real Time Clock you never need to reset the Nixie time display as the battery backup keeps current and accurate time. So if a power failure occurs or if you just wish to turn the Nixies off - no clock setting every time you turn your Nixies on. Just turn the power back on and the correct time and date are displayed.

Sample Nixie Clock Program in BASIC