User guide

122 www.xilinx.com Spartan-6 FPGA Configuration User Guide
UG380 (v2.7) October 29, 2014
Chapter 6: Readback and Configuration Verification
The packets shifted in to the JTAG CFG_IN register are identical to the packets shifted in
through the SelectMAP interface when reading the STAT register through SelectMAP.
Table 6-5: Status Register Readback Command Sequence (JTAG)
Step Description
Set and Hold # of
Clocks
(TCK)
TDI TMS
1
Clock five
1s on TMS to bring the device to the TLR state. X 1 5
Move into the RTI state. X 0 1
Move into the Select-IR state. X 1 2
Move into the Shift-IR state. X 0 2
2
Shift the first five bits of the CFG_IN instruction, LSB
first.
00101
(CFG_IN)
05
Shift the MSB of the CFG_IN instruction while exiting
SHIFT-IR.
011
Move into the SELECT-DR state. X 1 2
Move into the SHIFT-DR state. X 0 2
3
Shift configuration packets into the CFG_IN data
register, MSB first.
a:
0xAA99
a: 0x5566
b: 0x2901
c: 0x2000
c: 0x2000
d: 0x2000
d: 0x2000
0111
Shift the LSB of the last configuration packet while
exiting SHIFT-DR.
011
Move into the SELECT-IR state. X 1 3
Move into the SHIFT-IR state. X 0 2
4
Shift the first five bits of the CFG_OUT instruction, LSB
first.
00100
(CFG_OUT)
05
Shift the MSB of the CFG_OUT instruction while exiting
Shift-IR.
011
Move into the SELECT-DR state. X 1 2
Move into the SHIFT-DR state. X 0 2
5
Shift the contents of the STAT register out of the
CFG_OUT data register.
0xSSSS 015
Shift the last bit of the STAT register out of the CFG_OUT
data register while exiting SHIFT-DR.
S11
Move into the Select-IR state. X 1 3
Move into the Shift-IR State. X 0 2
6 Reset the TAP Controller. X 1 5