A 30 years old TMS7000 project measuring moved weigt per exersize and with cumulatieve result counter
In between can you folow your heartbeat on the result/KG display
If the user of the fitnes tool is a wheelchair user he can have a slave unit to folow up his exersizes
The kilos of the fitnesmachine is from a presurised cilinder. the presure can pumped up manualy and is measured bij a presure transduser
For AD conversion is a dual (triple )slope converter used, initialized bij te processor and measured by the interupt.
A serial interface is provided to send and recieve information from a slave unit.
the display and keyboard uses only a few io lines
and the computer uses a tricky debounce system that delivers flawless key up and key down. and is going almost direct to the place to run.