GUIDELINE: Design properly for OTG operation, when applicable.
When On-the-Go (OTG) functionality is used, the SoC can become a host or endpoint.
When in host mode consider the power delivery, such as when you are supporting a
USB Flash drive, or potentially a USB Hard Drive. These power requirements and
reverse currents must be accounted for, typically by using external diodes and current
limiters such as those used on the Cyclone V SoC or Arria V SoC development kits.
4.5.3. QSPI Flash Interface Design Guidelines
Up to four QSPI chip selects can be used with Cyclone V/Arria V SoC. The device can
boot only from QSPI connected to the chip select zero.
GUIDELINE: Ensure that the
QSPI_SS
signals are used in numerical order.
Intel Quartus Prime assumes that the
QSPI_SS
signals are used in order. It is not
possible to use
SS0
and
SS2
, for example, without using
SS1
.
Note:
Supported Flash Devices for Cyclone V and Arria V SoC
for a list of supported
QSPI devices. RocketBoards.org also provides useful information at
and
GSRD v13.1 - Programming QSPI Flash
GUIDELINE: If your design uses QSPI flash with 4-byte addressing, design
the board to ensure that the QSPI flash is reset or power-cycled whenever
the HPS is reset.
The HPS boot ROM on Cyclone V and Arria V runs in 3-byte address mode by default.
If the QSPI flash is switched to 4-byte addressing during operation, ensure that it is
returned to its default 3-byte addressing mode whenever the HPS is reset. Otherwise,
the HPS cannot boot from or access the QSPI flash memory device.
You can switch the QSPI to 3-byte addressing mode using one of the following
methods:
•
If the QSPI device has a reset pin, assert the reset signal every time the HPS
device is reset.
•
If the QSPI device does not have a reset pin, power-cycle the QSPI device every
time the HPS device is reset.
page of RocketBoards.org offers recommendations
for implementing the reset signal to the QSPI flash. For additional information, refer to
“Selecting QSPI Flash Devices” and “For QSPI and SD/MMC/eMMC Provide Flash
Memory Reset”.
Related Information
•
•
For QSPI and SD/MMC/eMMC Provide Flash Memory Reset
on page 31
•
Supported Flash Devices for Cyclone V SoC and Arria V SoC
4. Board Design Guidelines for SoC FPGAs
AN-796 | 2018.06.18
AN 796: Cyclone V and Arria V SoC Device Design Guidelines
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