小型数控测井系统I／O总线扩展设计

I/O Bus Extension of Small Computer-controlled Logging Systems

以ＰＣ机为背景提出了小型数控测井系统Ｉ／Ｏ总线的３种扩展设计方式：①串行异步方式，其结构简单，适应于数据量不大的小型系统；②并行同步方式，其信息传送速度快，编程、操作简单，适应于主机速度不太快的近距离连接；③并行异步方式，其可靠性高，传输距离长，能与各种不同速度的外部设备相连接。

Three methods for extending I/O buses of small computer-controlled logging systems on the basis of PCs are proposed. They are(1)serial asynchronous mode which is simple in structure and useful for small logging systems with a little data demand,(2) parallel synchronous mode which is fast in signal transmission and easy to program,suitable for small distance connection master computers with suitable speeds,and (3)parallel asynchronous mode which is capable of long-distance transmission and connection of peripherals with different speeds.