I'm designing a system which has many modules each with a Spartan 6 FPGA and all JTAG interfaces come to a central board which also has other JTAG programmable devices. A big JTAG chain around all isn't really practical (for example one module may not be fitted and cable lengths etc are long) so I'm considering using a JTAG switch type device such as a SCANSTA112 to select the appropriate chain and program the device or devices on that chain. There will only be one JTAG port on the outside of the unit and this needs to be able to update any of the devices. The company has a typical Xilinx Platform Cable USB II programmer. My question is: is there some scripting method or configuration within iMPACT to be able to tell a device such as the SCANSTA112 which chain to select such that the programmer can then program the correct Xilinx device configuration memory?