from commands.h:128
enum jtag_command_type
{
JTAG_SCAN = 1,
JTAG_TLR_RESET = 2,
JTAG_RUNTEST = 3,
JTAG_RESET = 4,
JTAG_PATHMOVE = 6,
JTAG_SLEEP = 7,
JTAG_STABLECLOCKS = 8,
JTAG_TMS = 9,
};