I
import
Unregistered / Unconfirmed
GUEST, unregistred user!
可用CREATEFILE以PRN为文件名生成一个文件，检测返回值，若成功则打印机可用，否则显示打印机故障。生成关于PRN的文件句柄后，可象普通文件一样向文件写入内容，比如WRITE，写完后关闭文件。
//从并行端口读取打印机状态
function GetPrinterStatus:byte;
asm
MOV DX,$379;
IN AL,DX;
end;
//获取打印机是否出错
function CheckPrinter:boolean;
var
temp:byte;
begin
temp:=GetPrinterStatus;
Result:=not ( ((temp and $80)=0) //打印机忙
or ((temp and $20)<>0) //打印机缺纸
or ((temp and $10)=0) //打印机未联机
or ((temp and $08)=0) ); //打印机出错;
end;
//从并行端口读取打印机状态
function GetPrinterStatus:byte;
asm
MOV DX,$379;
IN AL,DX;
end;
//获取打印机是否出错
function CheckPrinter:boolean;
var
temp:byte;
begin
temp:=GetPrinterStatus;
Result:=not ( ((temp and $80)=0) //打印机忙
or ((temp and $20)<>0) //打印机缺纸
or ((temp and $10)=0) //打印机未联机
or ((temp and $08)=0) ); //打印机出错;
end;