While trying to set up a Triangle or Sawtooth wave with a 12V amplitude from Zero I discovered that my chinesium function generators won't do it! First off, they don't have Sawtooth as a wave pattern. May be possible to program it as an arbitrary wave but not easily done on the fly. Secondly, they have a 20V max amplitude, OK there. But when you try to set a 12V amplitude with a 6V offset so it will be from 0 - +12V it clamps the amplitude to 8V. Best I can get out of them 8V amplitude using a 4V offset to set the bottom of the wave on zero. The only way to get +12V to 0 is to let them run the standard +12 to -12 full wave across zero. You can do that, but the timing may be off depending on what you are doing with that signal.