Zynq-7000 AP SoC and 7 Series FPGAs MIS v4.1
372
UG586 November 30, 2016
Chapter 2:
QDR II+ Memory Interface Solution
3. The current bit and byte being measured are indicated by the VIO signals
dbg_win_current_bit
and
dbg_win_current_byte,
respectively.
4. To get the left and right tap counts for a completed bit, select the desired bit using VIO
signal
dbg_win_bit_select
and observe the results on
dbg_win_left_ram_out
and
dbg_win_right_ram_out
, respectively.
lists the signals associated with this automated window checking functionality.
DEBUG_PORT Signals
The top-level wrapper,
user_top
, provides several output signals that can be used to
debug the core if the debug option is checked when generating the design through the MIG
tool. Each debug signal output begins with
dbg_
. The DEBUG_PORT parameter is always set
to OFF in the
sim_tb_top
module of the
sim
folder, which disables the debug option for
functional simulations. These signals and their associated data are described in
.
Table 2-17:
Debug Window Port Signals
Signal
Description
dbg_win_start
Single pulse that starts the chk_win state machine. Use the Vivado logic
debug VIO module to control this.
dbg_win_bit_select[6:0]
Manual bit selection for reporting of results. The results are provided
on dbg_win_left_ram_out and dbg_win_right_ram_out for the bit
indicated.
dbg_win_active
Flag to indicate chk_win is active and measuring read window margins.
While active, the state machine has control over the debug port
signals.
vio_dbg_clear_error
Clear error control signal controlled by chk_win.
dbg_win_current_bit[6:0]
Feedback to indicate which bit is currently being monitored during
automatic window checking.
dbg_win_current_byte[3:0]
Feedback to indicate which byte is currently being monitored (and
used to select the byte lane controls with dbg_byte_sel).
dbg_win_left_ram_out [WIN_SIZE – 1:0] PHASER_IN tap count to reach the left edge of the read window for a
given bit.
dbg_win_right_ram_out [WIN_SIZE –
1:0]
PHASER_IN tap count to reach the right edge of the read window for a
given bit.
dbg_pi_f_inc
chk_win control signal to increment PHASER_IN. This signal should be
used only when dbg_win_active is deasserted.
dbg_pi_f_dec
chk_win control signal to decrease PHASER_IN. This signal should be
used only when dbg_win_active is deasserted.