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Altera_Forum's avatar
Altera_Forum
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13 years ago

Configuration Data Confusion

I'm attempting to design a board for a Cyclone II device. I want to use an EPCS4

for the configuration data. I've read several Altera documents ("Configuring

Cyclone II Devices", "Serial Configuration Devices (EPCS1 & EPCS4) Data Sheet")

but I'm still confused about the different download modes. Could someone briefly

explain the difference between JTAG and Active Serial modes and the types of

hardware required for use with the Quartus II 12.0 Programmer.

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    13 years ago

    Never mind. I found the information I need in previous posts. I should have look before I posted.

  • Altera_Forum's avatar
    Altera_Forum
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    13 years ago

    With the JTAG mode you can program the FPGA without using the EPCS chip. It's a volatile configuration. You need reconfigure the FPGA each time you power off the system. With the active serial you just program the EPCS device. After this, this chip configures the FPGA.

    The JTAG signals ( TDI, TDO, TCK ) uses diffent pins that uses AS ( DCLK, DATA, ASDI, nCS ). This In all the PCB I draw I put both connectors.

    I tied MSEL1,0 to GND with 2 10K pull-down resistors for standard speed Active Serial.
  • Altera_Forum's avatar
    Altera_Forum
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    13 years ago

    Thanks for your reply.

    The post by dwh@ovro.caltech.edu, August 29, 2012, describes how the configuration data can be downloaded to the serial configuration device via the JTAG.