Cyclone® V Device Handbook: Volume 1: Device Interfaces and Integration

ID 683375
Date 10/18/2023
Document Table of Contents

7.10.3. CONFIG_IO JTAG Instruction

The CONFIO_IO JTAG instruction allows you to configure the I/O buffers using the JTAG port before or during device configuration. When you issue this instruction, it interrupts configuration and allows you to issue all JTAG instructions. Otherwise, you can only issue the BYPASS, IDCODE, and SAMPLE JTAG instructions.

You can use the CONFIO_IO JTAG instruction to interrupt configuration and perform board-level testing. After the board-level testing is completed, you must reconfigure your device. Use the following methods to reconfigure your device:

  • JTAG interface—issue the PULSE_NCONFIG JTAG instruction.
  • FPP, PS, or AS configuration scheme—pulse the nCONFIG pin low.