Altera ALTDLL - Manual (Page 48)

Chapter 4: Functional Description 4–12
ALTDQ_DQS Megafunction
© February 2012 Altera Corporation ALTDLL and ALTDQ_DQS Megafunctions User Guide
DQS Output/OE Path
This path sends the DQS strobe signal to the external memory for writing operations.
Figure 4–6 shows the available blocks in the DQS output and OE path and the
connections with the ALTDQ_DQS ports.
Figure 4–6. DQS Output and OE Path (Note 1) , (2) , (3)
Notes to Figure 4–6 :
(1) The dqs_output_data_out port must be connected to the input port of the output buffer.
(2) The dqs_oe_out port must be connected to the output enable port of the output buffer.
(3) The DQS_OE_HR_DDIO_OUT , DQS_OUTPUT_HR_DDIO_OUT_HIGH and DQS_OUTPUT_HR_DDIO_OUT_LOW blocks are half-rate
components.
DQS_OUTPUT_DELAY_CHAIN2 (D6)
IO_CONFIG
dqs_output_data_out
DQS_OUTPUT_DELAY_CHAIN1 (D5)
DQS_OUTPUT_FF
DQS_OUTPUT_DDIO_OUT
DQS_OUTPUT_HR_DDIO_OUT_HIGH
dqs_hr_output_data_in
dqs_output_reg_clk
dqs_areset
and
DQS_OUTPUT_HR_DDIO_OUT_LOW
dqs_sreset
dqs_areset
dqs_output_reg_clkena
dqs_output_reg_clk
DQS_OE_DELAY_CHAIN2 (D6)
IO_CONFIG
dqs_oe_out
DQS_OE_DELAY_CHAIN1 (D5)
DQS_OE_FF
DQS_OE_DDIO_OE
DQS_OE_HR_DDIO_OUT
dqs_hr_oe_in
dqs_hr_output_reg_clk
dqs_areset
dqs_sreset
dqs_areset
dqs_output_reg_clkena
dqs_output_reg_clk
dqs_output_data_in
dqs_output_data_in_high
dqs_output_data_in_low
and
DQS OUTPUT PATH
dqs_oe_in
DQS OE PATH