I think you mean can a DAC be used to control a 555 timer? In principle yes, but it would be a design exercise, not a straight forward "do this or that". The 555 is programmable by changing analogue values like R and C, while a DAC outputs voltage or current. A digitally programmable resistor (AD5246) is something like a DAC to consider.
Normally pulses as produced by a 555 timer can be easily produced using software or hardware in a micro-controller which would be no more difficult than programming a DAC. They usually have programmable timers built in, but even if not, software can control a digital output (and be triggered by a digital input) in much the same ways as a 555 timer. See the first link for an example of a counter timer intended to work with a bus connection to a computer.
If you wished to use other hardware like a counter or switches to change the settings instead of a computer device, there are simple digitally programmable timers that would be no more difficult to operate this way. A basic example is the CD4541 which has 3 programmable times or the CD4536 which has 16 times.
The question is difficult to understand, but mostly needs a big picture explanation of what you want to do. Maybe you want to run the output of the 555 to a counter and then use the counter to program the 555. This means the 555 in astable mode would be sweeping its frequency in a stepped sawtooth pattern as the counter rolls over. The same idea can be applied to programmable counters which are arranged to be self triggering. Also a sweep generator with square wave output is of limited value, considered a sweep generator is usually used for testing frequency response which needs a sine wave.