DE3 User Manual
10
2.2
JTAG Chain
This section describes how to setup the JTAG chain on DE3 board.
If the DE3 board is used without any board connected and all the positions in SW6 are switched to
OFF (i.e., down position), the JTAG-interface signals of all HSTC connectors are bypassed, as
shown in
Figure 2.3
.
When the top HSTC connector is not connected with any daughter board, the JTGA interface is
bypassed. If a daughter board is connected to the top HSTC connector, the JTAG interface will be
enabled automatically.
Figure 2.4
shows the JTAG chain with a daughter board connected to the
DE3 board via top HSTC connector A. Note that if the daughter board does not use the JTAG
interface, the TDI and TOD pins on the daughter board must be shorted for the JTAG signals to pass
through.
A four position DIP switch (SW6) on DE3 board is used to control the JTAG interface signals of
bottom HSTC connectors.
Table 2-1
indicates the detailed configurations of SW6. When the bottom
connector is connected with other DE3 board or an daughter board, users need to configure the
SW6 to connect the JTAG chain to other board accordingly.
Figure 2.5
shows there are two DE3
boards stacked, and the JTAG chain is established through HSTA connector A, as shown in
Figure
2.6
.
Table 2-1. DIP switch (SW6) setting for JTAG interface on bottom HSTC connectors
Position
Switch Setting
Turn OFF (lower position)
Turn ON (upper position)
1
Bypass the JTAG interface on
the Bottom HSTC connector A(J2)
Enable the JTAG interface for
Bottom HSTC connector A(J2)
2
Bypass the JTAG interface on
the Bottom HSTC connector B(J4)
Enable the JTAG interface for
Bottom HSTC connector B(J4)
3
Bypass the JTAG interface on
the Bottom HSTC connector C(J6)
Enable the JTAG interface for
Bottom HSTC connector C(J6)
4
Bypass the JTAG interface on
the Bottom HSTC connector D(J8)
Enable the JTAG interface for
Bottom HSTC connector D(J8)
Summary of Contents for Altera DE3
Page 1: ...Altera DE3 Board ...
Page 67: ...DE3 User Manual 64 Figure 5 5 Plug USB Devices into DE3 Figure 5 6 Display Device Information ...
Page 75: ...DE3 User Manual 72 Figure 5 14 Display SD Card Information for the SD Card Demonstration ...
Page 79: ...DE3 User Manual 76 Figure 5 19 Parameter Settings in DDR2 Controller ...
Page 114: ...DE3 User Manual 111 Figure D 5 The reported message of the invalid I O pins ...