求翻译：JMDM-COM40MR/MT串口控制继电器（晶体管）板是深圳市精敏数字机器有限公司自主研发的高可靠工业级控制器，可用于串口控制多路继电器（晶体管）的输出。可以2种模式工作：实时模式：通过电脑发送控制命令(可以是ASCII码或字符串)给控制器控制继电器的输出；程序模式：通过电脑发送控制程序给控制器，控制器保存程序，并根据程序和时间控制继电器输出。是什么意思？

JMDM-COM40MR/MT serial interface control relay (transistor) Board is Shenzhen Jing min digital machinery developed a highly reliable industrial controllers, can be used for serial port control multiple relays (transistor) output. 2 modes: real mode: sent via computer control commands (or string is the ASCII code) give controller control relay output; the program mode: sent via computer control program to the controller, controller saving program, and according to program and control relay outputs.