doc/FPGAs,doc/vendors/lattice: added Lattice ECP3

doc/FPGAs.yml

@@ -179,6 +179,12 @@ Lattice:
     Memory: OK
     Flash: OK
 
+  - Description: ECP3
+    Model: LFE3-70E
+    URL: https://www.latticesemi.com/Products/FPGAandCPLD/LatticeECP3
+    Memory: OK
+    Flash: TBD
+
   - Description: ECP5
     Model:
       - LFE5U-12

doc/vendors/lattice.rst

@@ -73,8 +73,8 @@ Bin file load:
 
 Since it's a direct access to the flash (SPI) the ``-b`` option is required.
 
-ECP5/Crosslink-NX
-=================
+ECP5/ECP3/Certus-NX/CertusPro-NX/Crosslink-NX
+=============================================
 
 SRAM
 ----
@@ -89,6 +89,10 @@ SRAM
 SPI Flash
 ---------
 
+.. note::
+
+   SPI Flash write is not supported for ECP3 family.
+
 BIT:
 
 .. code-block:: bash