Altera Dynamic Calibrated On-Chip Termination User Manual
Page 12
Chapter 3: Functional Description
3–5
Verify Termination or Calibration Assignments of the Design Example
February 2012
Altera Corporation
Dynamic Calibrated On-Chip Termination (ALTOCT) Megafunction
User Guide
Verify Termination or Calibration Assignments of the Design Example
This section describes the necessary assignments for the design example. Perform the
following steps to verify the assignments.
1. In the Quartus II software, on the Assignments menu, click Assignment Editor.
The Assignment Editor appears.
shows the assignments used in the design example.
The first set of assignments are I/O Standard assignments that are used on the
pins of the design. This selection depends on which I/O standards are valid for a
particular application. In this design example, the functional output pins are
test_output[3..0]
, which are all assigned the SSTL-18 Class 1 standard.
The second set of assignments are Output Termination assignments that are
assigned to pins that have termination. You can specify the assignments as
non-calibrated termination or calibrated termination. In this design example, the
functional output pins are
test_output[3..0]
, which are all assigned the Output
Termination assignments with the value of Series 50 Ohm with Calibration. In
this assignment, these pins function as outputs for the FPGA chip only.
The third set of assignments are Termination Control Block assignments that are
used to indicate which calibration block is used to calibrate a particular I/O pin or
group. In this design example, the functional output pins are
test_output[3..0]
,
which are assigned with the value of
cal_out:inst|cal_out_alt_oct_q8n:cal_out_alt_oct_q8n_component|sd1a_x
,
where
x
indicates the termination calibration block that is used. Becausethe output
pins,
test_output[3..0]
, are four bits, each bit of the pin is assigned to one
calibration block.
2. Verify that all the assignments in the Assignment Editor match what is shown in
Figure 3–2. Assignments Used in the altoct_ex Design