@item @var{ir} ... is loaded into the JTAG IR to map the flash as the JTAG DR.
For the bitstreams generated from @file{xilinx_bscan_spi.py} this is the
@var{USER1} instruction.
-@item @var{dr_length} ... is the length of the DR register. This will be 1 for
-@file{xilinx_bscan_spi.py} bitstreams and most other cases.
@end itemize
@example
target create $_TARGETNAME testee -chain-position $_CHIPNAME.fpga
set _XILINX_USER1 0x02
-set _DR_LENGTH 1
flash bank $_FLASHNAME spi 0x0 0 0 0 \
- $_TARGETNAME $_XILINX_USER1 $_DR_LENGTH
+ $_TARGETNAME $_XILINX_USER1
@end example
@end deffn