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Altera_Forum's avatar
Altera_Forum
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14 years ago

cyclone 1 with byteblaster

i am using altera cyclone 1 with byteblaster cable if the bank containing jtag pins has vccio 2.5v so i will have to connect the vcctarget of jtag to 2.5v

and if so the input minimum voltage of jtag equal vcc-0.2 (2.3) while the fpga minimum output voltage 2.1 so what can i do ?

thanks in advance

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    Byteblaster II and USB Blaster have been designed to handle these low IO voltages. Original ByteBlaster requires a 5V supply according to the utilized 74LS driver, ByteBlasterMV needs at least 3.3V supply, altough VCCIO can be lower. Read the comments in the respective ByteBlaster datasheets. A possible solution could be an on-board voltage translation buffer for TDO.

    Do you have a 3.3V supply available on the board?
  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    in the datasheet of byteblasterMV the vcc may be 5 or 3.3 or 2.5 so it does not need at least 3.3v supply ,is that right?