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Altera_Forum
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14 years ago

JTAG programming of MAX V and Cyclone IV

Hi I want to put both a MAX V and Cyclone IV on the same JTAG chain so they can both be programmed via a USB blaster. VCCIO for both devices is +3.3V. From the manuals the MAX V needs a +3.3V s...
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Altera_Forum
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14 years ago

Altera devices use the four JTAG pins for JTAG programming or configuration. They should be connected as below:

  1. TCK (Test Clock) - From download cable in parallel to every device in the JTAG chain. Weakly pulled-down to GND. Check the Configuration Handbook or specific device Handbook for resistor values.

  2. TMS (Test Mode Select) - From download cable in parallel to every device in the JTAG chain. Weakly pulled-up to VCCIO. Check the Configuration Handbook or specific device Handbook for resistor values.

  3. TDO (Test Data Out) - The TDO pin of a device is connected to the TDI pin of the subsequent device in the JTAG chain. For the last device in the JTAG chain, the TDO pin is connected to the TDO pin of the download cable.

  4. TDI (Test Data In) - TDI pin of a device is connected to the TDO pin of the preceding device in the JTAG chain. For the first device in the JTAG chain, the TDI pin is connected to the TDI pin of the download cable.

Even though other programming or configuration pins (for FPGA) are not used in JTAG mode, they must be properly connected and cannot be left floating.

  1. nTRST - Driven high during JTAG configuration.

  2. nCE - Connect to GND or driven low during JTAG configuration.

  3. MSEL pins - Connect to ground.

  4. nCONFIG - Driven high or pulled to VCC through a pull-up resistor.

  5. DCLK - Either pull-up or pull-down through resistor.

  6. DATA pin(s) - Either pull-up or pull-down through resistor.

  7. nSTATUS - Pull to VCC through a pull-up resistor. When the device is powered-up, this pin will be released to high.

  8. CONF_DONE - Pull to VCC through a pull-up resistor. Should be pulled-up individually for the devices in a chain. When the device is successfully configured, this pin will be released to high.

  9. INIT_DONE - When used, pull-up to VCC.