ublast_queue_tdi() function

ublast_queue_tdi - short description Outputs a series of TDI bits on TDI. As a side effect, the last TDI bit is sent along a TMS=1, and triggers a JTAG TAP state shift if input bits were non NULL. In order to not saturate the USB Blaster queues, this method reads back TDO if the scan type requests it, and stores them back in bits. As a side note, the state of TCK when entering this function *must* be low. This is because byteshift mode outputs TDI on rising TCK and reads TDO on falling TCK if and only if TCK is low before queuing byteshift mode bytes. If TCK was high, the USB blaster will queue TDI on falling edge, and read TDO on rising edge !!!