gres
Full Member level 4
Depends on button that is pressed it display running text thanks to 85 multiplex diodes LED. It can be use also as a normal display for discreetly message sending. Thanks to small dimensions you can take it anywhere. Thanks to using microcontroller ATmega88V current consumption and required voltage are very low. That processor works with 1,8V, and on stand by mode needs only 1uA ( all device 1,5uA). LEDs work with 2V, so after discharge battery ( less then nominally 3V) tool still can work. After install new battery we can see welcome communicate, and battery level ( check to 3,44V with precision 0.01V.
Text can be set by editor, and storage in eeprom memory of microcontroller. 512B memory can remember up to 4 texts with 127 marks each (128th cell is used to collect special mark = text end). Device have also a few options that can be changed by short pressing button:
1- scrolling text speed (slower / faster)
2 - text display as a negative (normal / negative)
3 - switch between small / LARGE litters
4 - text editor. Firstly we can choose text, than edit: button 1 - previous mark 2- next mark 3 - next mark 4 - text save.
Device is set to stand by mode, after pressing any button, text appear. Pressing another button couse instant flash right text.
Display is a 85 diodes in 0805 casings. 5rows by 17 diodes.
Dimmensions: 24mmx85mmx5mm. Three of paths at diodes side you need to make by very thin wire ( isolate by lacquer). Battery holder I made from another holder type. There is no programming slot. Three first grummets (from battery side) are mosi miso and sck lines, reset line is a "testpoint". Grummets made by thin wire, drill 0,6mm and both sides solder . Program I wrote in bascom, object code has about 6,2kB
More information at https://www.elektroda.pl/rtvforum/topic1448112.html?sid=b34518b8c9211cf7ed840d18b777dd94