AN 822: Intel® FPGA Configuration Device Migration Guideline

ID 683340
Date 4/29/2020
Document Table of Contents
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1.1. Migration Considerations

The EPCQ-A devices are conditionally compatible for a direct migration from EPCQ and EPCS devices.

You must consider the following items to determine the compatibility and the next step of action for a successful device migration.

IP Cores

If you are using Intel® IP cores, you may need to regenerate and recompile your design. In certain conditions, the programming files can be reused without recompilation. Refer to IP Core Compatibility for more information about IP core compatibility. Refer to Table 3 if you are not using IP cores that interface with the configuration device.

Pins, Package and Capacity

Migration can only be done to an EPCQ-A device that has sufficient capacity for the programming file and have the same pin count package.

Pin 3 (nRESET) on the EPCQ64A and EPCQ128A devices act as a reset pin. This pin has an internal pull-up, and if you do not use the reset function, connect the nRESET pin to either VCC or leave it unconnected. Refer to Pin Information for more information about the pin-outs and descriptions.

Figure 1. EPCS to EPCQ Migration Pin Package and Capacity Summary

Operation Commands

The dummy clock requirement of the fast read (0Bh) and extended quad input fast read (EBh) commands:

  • EPCQ—the dummy clock is configurable with the non-volatile configuration register (NVCR). When the EPCQ is used with a Cyclone® V, Arria® V or Stratix® V device, the dummy clock is configured to be 4, 10 or 12, depending on the byte-addressing mode and ASx1 or ASx4 configuration. However, in EPCQ-A devices, the dummy clock is fixed at 8 and 6 for fast read and extended quad input fast read respectively. Therefore you must regenerate the programming files, such as .pof, .jic, and .rpd.
  • EPCS—the dummy clock is fixed at 8 for fast read, therefore you do not have to regenerate the programming files if all other conditions are met. Table 3 defines the need to regenerate the programming files. Refer to IP Core and Programming File Migration Guideline for more information about the conditions.

Status Register

Status Register contains the Top/Bottom (TB) bit (bit 5), Block Protect (BP) bits (bit 4, bit 3, bit 2) for sector protection bits. EPCS devices do not have TP bit and some EPCQ device densities have BP3 (bit 6), while bit 6 is reserved in EPCQ-A devices. Due to this differences, you may need to recompile the programming file if your design uses the sector protect feature. Refer to Status Register for more information about status registers and sector protect bits.

Sector Size

All of the EPCS, EPCQ and EPCQ-A devices have the sector size of 512kb except for EPCS128 which has 2Mb. This impacts the sector erase operation. If the design is erasing the flash during user mode, you must update your design to comply the sector size when migrating from EPCS128 to EPCQ128A. After updating your design, regenerate a new programming file for the EPCQ-A device.