EPC4 datasheet(14/34 Pages) ALTERA

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Chapter 1: Enhanced Configuration Devices (EPC4, EPC8, and EPC16) Data Sheet

Functional Description

Configuration Handbook (Complete Two-Volume Set)

Altera Corporation

1 The external flash interface signals cannot be shared between multiple enhanced

configuration devices because this causes contention during in-system programming

and configuration. During these operations, the controller chips inside the enhanced

configuration devices are actively accessing flash memory. Therefore, enhanced

configuration devices do not support shared flash bus interfaces.

The enhanced configuration device controller chip accesses flash memory during:

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FPGA configuration—reading configuration data from flash

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JTAG-based flash programming—storing configuration data in flash

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At POR—reading option bits from flash

During these operations, the external FPGA or processor must tri-state its interface to

the flash memory. After configuration and programming, the enhanced configuration

device’s controller tri-states the internal interface and goes into an idle mode. To

interrupt a configuration cycle in order to access the flash via the external flash

interface, the external device can hold the FPGA’s nCONFIG input low. This keeps the

configuration device in reset by holding the nSTATUS-OE line low, allowing external

flash access.

f For more information about the software support for the external flash interface

feature, refer to the Altera Enhanced Configuration Devices chapter in volume 2 of the

Configuration Handbook. For details about flash commands, timing, memory

organization, and write protection features, refer to the following documents:

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For Micron flash-based EPC4, refer to the Micron Flash Memory MT28F400B3 Data

Sheet at www.micron.com.

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For Sharp flash-based EPC16, refer to the Sharp LHF16J06 Data Sheet Flash Memory

Used in EPC16 Devices at www.sharpsma.com.

■

For the Intel Advanced Boot Block Flash Memory (B3) 28F008/800B3, 28F016/160B3,

28F320B3, 28F640B3 Datasheet, visit www.intel.com.

EPC4 Datasheet(PDF) 14 Page - Altera Corporation