说明：  通用宽行打印机检测及打印程序PPRNT（如SENTRONICS标准并行接口的EPSON LQ-570型，FX-800型） 入口条件：设定外部中断（INT1)服务引导和开中断EA=1；欲打印数据放在片外 RAM中，首地址放在片内RAM双字节71H，72H中； ；；每行打印数据以CR和LF命令分割；以03为打印结束标志。 ；；出口条件：EX1=0时，打印结束
(Universal wide-line printer detection and print program PPRNT (such as SENTRONICS standard parallel interface EPSON LQ-570 type, FX-800 type) inlet conditions: Set external interrupt (INT1) service guide and open interrupt EA = 1 want to print data on-chip RAM, the first on-chip RAM address double-byte 71H, 72H in each line of print data to CR and LF commands segmentation to 03 for the print end marker. Export conditions: EX1 = 0, the print end of the)