论文部分内容阅读
故障现象一台COMPAQ 386微机,软、硬盘控制器及串、并口都制作在主板上。当把打印机与微机通过并行口相连,微机启动后,在西文状态下,不能打印。故障分析与排除打印机及电缆线已经确认没有故障,故障出在主板上的并行口上,它的口地址为3BCH。因该并行口制作在主板上,对它进行维修比较麻烦。为了使该机打印正常,在主板的I/O插槽中插上一块单独的打印卡,其并行口地址为378H,同时还必须使主板上的并行口的译码电路不能工作,需要处理主板上的并行口的译码电路。为了在不动主板的情况下也能正常打印,在打印前,把数据区O∶408H与O∶40AH地址的内容BC与78交换一下,具体操作如下:C> DEBUG
Symptom A COMPAQ 386 computer, soft, hard disk controller and serial, parallel port are produced on the motherboard. When the printer and the computer connected through parallel port, the computer starts, in the Western state, can not print. Fault Analysis and Troubleshooting Printers and cables have been confirmed no fault, the fault is on the parallel port on the motherboard, its port address 3BCH. Because of the parallel port produced on the motherboard, it is too much trouble to repair it. In order to print the machine normal, plug in the motherboard I / O slot a separate print card, its parallel port address 378H, but also must make the parallel port on the motherboard decoding circuit does not work, you need to deal with the motherboard On the parallel port of the decoding circuit. In order to print the case can not be normal, before printing, the contents of the data area O: 408H and O: 40AH address BC exchange with 78, the specific operation is as follows: C> DEBUG