Michael Kern wrote:

"AT89C4051. There is too less code and data space to use SDCC, so all needs to be assembly written..."


On my web you can see an application written in C, which fits even into the smaller AT89C2051.

Nevertheless it contain lots of functions:
- clock (time, date) synchronized by the DCF-77
- alarm timer
- 2 min / max thermometers
- LED-display

Please look at:
http://www.specs.de/~danni/ap.../index.htm


Code efficiency was not a question of C vs. assembler.

Peter