Zynq-7000 AP SoC and 7 Series FPGAs MIS v4.1
74
UG586 November 30, 2016
Chapter 1:
DDR3 and DDR2 SDRAM Memory Interface Solution
vio_modify_enable
Input
Allow vio_xxxx_mode_value to alter traffic pattern.
vio_data_mode_value[3:0]
Input
Valid settings for this signal are:
• 0x0: Reserved.
• 0x1: FIXED – 32 bits of fixed_data as defined through
fixed_data_i inputs.
• 0x2: ADDRESS – 32 bits address as data. Data is generated based
on the logical address space. If a design has a 256-bit user data
bus, each write beat in the user bus would have a 256/8 address
increment in byte boundary. If the starting address is 1,300, the
data is 1,300, followed by 1,320 in the next cycle. To simplify the
logic, the user data pattern is a repeat of the increment of the
address value Bits[31:0].
• 0x3: HAMMER – All 1s are on DQ pins during the rising edge of
DQS, and all 0s are on the DQ pins during the falling edge of
DQS, except the VICTIM line as defined in the parameter
“SEL_VICTIM_LINE.” This option is only valid if parameter
DATA_PATTERN = “DGEN_HAMMER” or “DGEN_ALL.”
• 0x4: SIMPLE8 – Simple 8 data pattern that repeats every 8 words.
The patterns can be defined by the “simple_datax” inputs.
• 0x5: WALKING1s – Walking 1s are on the DQ pins. The starting
position of 1 depends on the address value. This option is only
valid if the parameter DATA_PATTERN = “DGEN_WALKING” or
“DGEN_ALL.”
• 0x6: WALKING0s – Walking 0s are on the DQ pins. The starting
position of 0 depends on the address value. This option is only
valid if the parameter DATA_PATTERN = “DGEN_WALKING0” or
“DGEN_ALL.”
• 0x7: PRBS – A 32-stage LFSR generates random data and is
seeded by the starting address. This option is only valid if the
parameter DATA_PATTERN = “DGEN_PRBS” or “DGEN_ALL.”
• 0x9: SLOW HAMMER – This is the slow MHz hammer data
pattern.
• 0xA: PHY_CALIB pattern – 0xFF, 00, AA, 55, 55, AA, 99, 66. This
mode only generates READ commands at address zero. This is
only valid in the Virtex
®
-7 family.
vio_addr_mode_value[2:0]
Input
Valid settings for this signal are:
• 0x1: FIXED address mode. The address comes from the
fixed_addr_i input bus. With FIXED address mode, the
data_mode is limited to the fixed_data_input. No PRBS data
pattern is generated.
• 0x2: PRBS address mode (Default). The address is generated
from the internal 32-bit LFSR circuit. The seed can be changed
through the cmd_seed input bus.
• 0x3: SEQUENTIAL address mode. The address is generated from
the internal address counter. The increment is determined by the
user interface port width.
Table 1-13:
Traffic Generator Signal Descriptions
(Cont’d)
Signal
Direction
Description