Under this article using xilinx FPGA , a process is only to implement a upsample factor of 4 ,a 16 FIR filter coefficients are used, so what if a upsamle factor is 10 , is it need to use 100 fir filter coefficients ?
No. FIR filter coefficients count is independent of sampling rate. It depends on filter characteristic.
But if you change sampling rate you need to adjust filter coefficients (value) to get the same filter characteristic.