Does the Maxim DS18S20 stop converting temperature if a reset is sent during the conversion?
(Note that I'm using the newer DS18B20 data sheet, but the differences should be minimal, especially regarding to the 1-Wire protocol as the devices are supposed to be compatible.)

Doing anything on the bus is explicitly forbidden if you are using parasite power:


  If the DS18B20 is powered with parasite power /.../ the bus must be pulled high by a strong pullup during the entire temperature conversion.


On the other hand, if you are using an external power supply, the data sheet states:


  the 1-Wire bus is free to carry other traffic during the temperature conversion time.


Furthermore, they give an example in the data sheet where you can actively poll whether the conversion process has finished.

This seems to suggest that you can use 1-Wire bus to communicate with other devices -- which implies that you would be able to send a reset pulse -- unless you are using parasite power. I wasn't able to find anything that directly confirms this, so it may be best if you try it out on a breadboard.