>If the JTAG Chain contains more than 3 devices, it is recommended to add buffers to the Chain. In addition, it is necessary to clear the drive capacity, the influence of noise, and the regulation timing and violations.

For the buffer, please search for the keyword "Programming via a Download Cable" from the Device Handbook at the URL link below.
　https://www.altera.co.jp/en_JP/pdfs/literature/hb/max2/max2_mii5v1_04.pdf

For JTAG timing specifications, please refer to the Device Handbook at the URL link below and search for the keyword "MAX II JTAG Timing Parameters".
　https://www.altera.com/en_US/pdfs/literature/hb/max2/max2_mii51005.pdf