The actual use of these screens is taking shape. I am nearing completion of a working prototype but their are a few issues to iron out before I upload a video to youtube. For now here is a picture of the setup and a description of the project.
1-Wire 16 character 16 segment display. Powered via standard 5V the on board AVR (Tiny25) runs a boost converter via PWM to generate 35V to run the screen at a very bright level. Control is through the 1-Wire protocol but the device is not powered by it like many 1-Wire chips are due to the fact this board will draw ~200mA (maybe less). I wish to setup a control scheme to allow software brightness control and an easy method of sending ascii characters and what digit to display it on.
Issues so far include a pain in the ass Timer1 that refuses to enter its OVF interrupt (needed for multiplexing), I forgot the shift regs had a strobe for latching data so I am one pin short. I originally planned on I2C and have that working (mostly) but with the strobe tied high all of the character segments are lit and its hard to read. I don’ t want to write my own 1-Wire software library, the Tiny25 has a USI but I have never used one so it will be ‘interesting’ to learn.
Hopefully by the end of the week I will have it working and a video to show!