Update README.md

Radme.md: added WinCUPL user's manual link

README.md

@@ -23,6 +23,7 @@ Supported GAL chips:
 * Lattice GAL16V8A, GAL16V8B, GAL16V8D
 * Lattice GAL22V10B
 * National GAL16V8
+* Lattice GAL20V8B via [adapter board](https://github.com/ole00/afterburner/raw/master/img/gal20v8_adapter.png)
 
 **Please note that ATF16V8C or ATF16V8CZ are not currently supported.** Yes the B/C at the end of the part designator seems like a minor thing but in fact the programming protocol seems to be different compared to the B version (which is supported). Keep it in mind when ordering parts.  
 
@@ -94,7 +95,7 @@ Setup:
 
 How aferburner works:
 ---------------------
-- PC code reads and parses .jad files, then produces a binary which
+- PC code reads and parses .jed files, then produces a binary which
   can be then uploaded to Arduino via serial port. By default
   /dev/ttyUSB0 is used, but that can be changed to any other device
   by passing the following option to afterburner:
@@ -262,7 +263,22 @@ Troubleshooting:
 
 - what are the .jed files and how to produce them
   
-  * Use WinCupl software from Atmel. Works under Wine as well.
+  * Use WinCUPL software from Atmel. Works under Wine as well.
   
   https://www.microchip.com/design-centers/fpgas-and-plds/splds-cplds/pld-design-resources
   
+  * WinCUPL User's manual: http://ww1.microchip.com/downloads/en/DeviceDoc/doc0737.pdf
+  
+  * Try GAL Asm to produce .jed files - see link bellow.
+  
+Other GAL related links:
+------------------------
+- GAL chip info: https://k1.spdns.de/Develop/Projects/GalAsm/info/galer/gal16_20v8.html
+
+- GAL chip programming protocol info: https://k1.spdns.de/Develop/Projects/GalAsm/info/galer/proggal.html
+  
+- JDEC file standard 3A: https://k1.spdns.de/Develop/Projects/GalAsm/info/JEDEC%20File%20Standard%203A.txt
+  
+- GAL Asm : https://github.com/dwery/galasm
+ 
+- CUPL Reference: http://ee.sharif.edu/~logic_circuits_t/readings/CUPL_Reference.pdf