Merge branch 'master' of https://github.com/wybren1971/fluxengine into wybren1971-master

doc/using.md

@@ -1,4 +1,4 @@
-Using a FluxEngine
+Using a FluxEngine
 ==================
 
 So you've [built the hardware](building.md), programmed and tested it! What
@@ -140,6 +140,29 @@ exact format varies according to the extension:
 	read, but not yet written. You only get the data; the density and DAM bits
 	are ignored.
 
+  - `.imd`: a disk image format created by [David Dunfield](http://dunfield.classiccmp.org/img/index.htm).
+	These images can be used as input image for writing a disk. If you don’t 	know the diskformat, Fluxengine will show the stored comment and display 	the geometry to use. Just give a command like:
+
+    ```
+    $ ./fluxengine write ibm -i filenaam.imd
+	Comment in IMD image:
+	*** DOUBLE SIDED FORMAT ***                                   
+	HP-IB,RS-232C & RS-449 PREPROCESSOR                           
+	For HP1650A, HP1651A & HP16500A                               
+	10342-13017                                                   
+	Rev 2749 Ver 1.1                                              
+	Copyright (c) 1987, Hewlett-Packard                           
+                                                              
+                                                               
+	reading IMD image
+	77 tracks, 2 heads; MFM; 250 kbps; 5 sectoren; sectorsize 1024; sectormap 	12345; 770 kB total 
+	Writing to: :d=0:s=0-1:t=0-79
+  	0.0: Error: track data overrun
+    ```
+ 	
+	For input files you normally have to specify it yourself. So in this case  	append `:c=76:h=2:s=5:b=1024` to set the geometry.
+
+
 ### High density disks
 
 High density disks use a different magnetic medium to low and double density