while {[string equal "4" $pwrsts] && $i<20} {
irscan $_CHIPNAME.jrc 0x3a
drscan $_CHIPNAME.jrc 4 0;
set pwrsts [drscan $_CHIPNAME.jrc 16 0]
while {[string equal "4" $pwrsts] && $i<20} {
irscan $_CHIPNAME.jrc 0x3a
drscan $_CHIPNAME.jrc 4 0;
set pwrsts [drscan $_CHIPNAME.jrc 16 0]