Altera FIR Compiler - Manual (Page 71)

Appendix A: FIR Compiler Supported Device Structures A–3
Support for HardCopy Series Devices
© May 2011 Altera Corporation FIR Compiler User Guide
Support for HardCopy Series Devices
Preloaded RAM can be used by the other supported device families in tapped delay
line (for data storage) or for coefficient storage in reloadable FIR filters. However,
devices in the HardCopy
® series of devices (HardCopy II, HardCopy III,
HardCopy IV E, and HardCopy IV GX) do not support preloaded RAM elements.
Preloaded RAM is used by the other devices if you select M512 or M4K for data
storage (or if you select Auto, the Quartus
® II software selects M512 or M4K) and the
memory is automatically preloaded with zeros. Preloading cannot be done for
HardCopy devices.
For HardCopy devices, you must flush the memory by preceding your real data with
n zeros when loading the data into memory, and then discard the corresponding n
outputs.
The following formula describes the required number of preloaded zeroes:
n = number of channels × number of coefficients
Preloaded RAM may also be used by the other device families if you select M512 or
M4K
for the coefficient storage of reloadable FIR filters. This RAM cannot be
preloaded in HardCopy devices, and you must implement the logic to initialize or
update the coefficients. This can be done on-chip or by using the coefficient reordering
program (coef_esq.exe) included in the <install path>\fir_compiler\misc directory
and described in the section
“Coefficient Reloading and Reordering” on page 4–4 .
Compiling HardCopy Designs
When you store your data in memory or you store your coefficients in memory and
reload them, you must delete the memory initialization files described below before
you can successfully compile a HardCopy design in the Quartus II software.
If you are storing data in memory, to successfully compile your design in the
Quartus II software, you must delete the following file from the project directory
before compiling your design:
<variation name>_zero.hex
If you store your coefficients in memory and reload them, to successfully compile
your design in the Quartus II software, you must delete the following file from the
project directory before compiling your design:
< variation name>_coef_X.hex (where X is an integer)
These files are created by the FIR Compiler and are stored in the project directory you
specified when you ran the FIR Compiler.