Altera ALTDLL - Manual (Page 44)

Chapter 4: Functional Description 4–8
ALTDQ_DQS Megafunction
© February 2012 Altera Corporation ALTDLL and ALTDQ_DQS Megafunctions User Guide
DQ Input Path
This path receives the DQ signal from the external memory during read operations.
Instantiate this path for all input-only and bidirectional DQ I/O pins.
Figure 4–4
shows the available blocks in the DQ input path and the connections with the
ALTDQ_DQS ports.
1
The value for depends on your selection in the parameter editor. The possible
values are
BIDIR_DQ and INPUT_DQ .
Figure 4–4. DQ Input Path (Note 1) , (2) , (3)
Notes to Figure 4–4 :
(1) The _input_data_in port must be connected to the output port of the input buffer.
(2) The dll_delayctrlin port must be connected to the DLL.
(3) The IO_CLOCK_DIVIDER , _HALF_RATE_INPUT , _IPA_LOW , and _IPA_HIGH blocks are half-rate components.
_INPUT_DELAY_CHAIN (D1)
_INPUT_FF
_DDIO_IN
_IPA_LOW and _IPA_HIGH
dq_input_reg_clk
dqs_bus
dqs_input_reg_clkena
_areset
_sreset
DQS_CONFIG
_CONFIG
_HALF_RATE_INPUT _hr_input_data_out
dq_ipa_clk
dll_delayctrlin
_sreset
IO_CLOCK_DIVIDER
_input_data_out_low
_input_data_out_high
_input_data_out
_input_data_in
and
DQ Input Path