In order to realize the output of 16-channel control instructions of ground test equipment and complete the automatic drive control of the equipment under test, an automatic design of 16-channel control instruction output system integrated in PXI chassis is proposed based on constant current output and FPGA. Based on the traditional constant voltage output, LT3082 is introduced to design the constant current source output, and the closed-loop control of the equipment is completed through the design of self-checking circuit and alternative output; based on PXI architecture, FPGA is used as the main control chip, and all 16 control instructions can be configured to output independently, which can be combined with the self-checking circuit to check the working status of the equipment and the output status of the instructions. The experimental results show that the design realizes the functions of timing on-off, pulse output, system self-test and state query based on constant current output.