Radio-frequency driven atmospheric pressure plasmas are efficient sources for the production of reactive species at ambient pressure and close to room temperature. Pulsing the radio-frequency power input provides additional control over species production and gas temperature. Here, we demonstrate the controlled production of highly reactive atomic oxygen and nitrogen in a pulsed radio-frequency ( ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn001.gif] 13.56 MHz) atmospheric-pressure plasma, operated with a small ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn002.gif] 0.1 % air-like admixture ( ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn003.gif] \rm N_2 / ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn004.gif] \rm O_2 at ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn005.gif] 4:1 ) through variations in the duty cycle. Absolute densities of atomic oxygen and nitrogen are determined through vacuum-ultraviolet absorption spectroscopy using the DESIRS beamline at the SOLEIL synchrotron coupled with a high resolution Fourier-transform spectrometer. The neutral-gas temperature is measured using nitrogen molecular optical emission spectroscopy. For a fixed applied-voltage amplitude (234?V), varying the pulse duty cycle from 10% to 100% at a fixed 10?kHz pulse frequency enables us to regulate the densities of atomic oxygen and nitrogen over the ranges of ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn006.gif] (0.18±0.03) ? ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn007.gif] (3.7±0.1)× 10^20 ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn008.gif] \rm m^-3 and ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn009.gif] (0.2±0.06) ? ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn010.gif] (4.4±0.8) × 10^19 ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn011.gif] \rm m^-3 , respectively. The corresponding 11?K increase in the neutral-gas temperature with increased duty cycle, up to a maximum of ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn012.gif] (314±4) K, is relatively small. This additional degree of control, achieved through regulation of the pulse duty cycle and time-averaged power, could be of particular interest for prospective biomedical applications.