It looks like JTAG is supported for the Radar. The SLDROemMenu.exe has the folowing in it:
BSPBCFG512KB1024KB5MB20MB???0x8047E2 - Default0xC007E7 - Perf0x8147E6 - Boot0x000222 - PowerSerialSerial then QXDMJTAG(DCC4)JTAG(DCC4) then QXDMNo
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