added data slice primitive

dataflow_neuro/primitives.act

@@ -33,6 +33,9 @@ import "../../dataflow_neuro/treegates.act";
 import std::channel;
 open std::channel;
 
+// import std::func;
+
+
 namespace tmpl {
     namespace dataflow_neuro {
 
@@ -829,7 +832,32 @@ namespace tmpl {
             )
 
         }
+/**
+* Drops bits. Slices lines. Crop in. Enhance.
+* Useful if say, have an 8 bit packet coming in, but 
+* receiver only needs 3 of them.
+* KEEPS all bits between the two bounds.
+* e.g. drop_lines(8, 0, 3) would keep lines [0,1,2]
+**/
+export template<pint N, N0, N1>
+defproc slice_data(avMx1of2<N> in; avMx1of2<std::min(N1,N)-std::max(N0,0)> out; power supply) {
+    // {N0 >= 0 : "N0 can be minimum 0!"};
+    // {N1 <= N : "N1 can be maximum N"};
 
+    pint _N1, _N0;
+
+    _N1 = std::min(N1,N);
+    _N0 = std::max(N0,0);
+
+    BUF_X1 ack_buf(.a = out.a, .y = in.a, .vss = supply.vss, .vdd = supply.vdd);
+
+    vtree<N> in_vt(.in = in.d, .out = in.v, .supply = supply);
+    (i:_N1-_N0:
+        in.d.d[i + _N0] = out.d.d[i];
+    )
+
+    in.a = out.a;
+}