SWDIO/nRESET pin "debug mode"

Hello,

after programming the nrf51822 the SWDIO/nRESET pin is in "debug mode", to resume the normal mode the SWDCLK and SWDIO/nRESET line shuold low for a minimum of 100 μs (nRF51 Series Reference Manual). But with this procedure, I can not get into the normal mode. If i do a pinreset from the debugger (cmd line: "nrfjprog --pinreset") and look at SWDIO/nRESET line with an oscilloscope, an entire sequence of resets is triggered. What I have to do, to go back in the normal mode, if i don't want to do a power cycle?