I want to draw a dash line using line type, dash should be 3mm and spacing should be 1mm, what do you think?

Use this code into the file name acad.lin

*DASHED,Dashed (ASH) __ __ __ ___ __ __ __ __ __ __ __ __ _

A,3,-1

I agree with mohammed boram ....... good job

Agree with mr.Ahmed

*****************************

Mr. Ahmed Shawky answered this in a very brief manner.

Thanks.

i agree with eng/Ahmed shawky

In the command line write LT for linetype & from the dialogue that appears press LOAD then choose the required line type, finally press show details  to modify your linetype settings as per your requirements

I agree with Mr. Ahmed Shawky. Well explained. Works in both acad & acadISO template.