synapse handshake unit tests working

dataflow_neuro/coders.act

@@ -214,14 +214,20 @@ namespace tmpl {
 			)
 
 			// req-ack buffers
+			// Delay needed here, since otherwise the pull up of reqB happens too quickly.
+			// Means that the pull up may start fighting the synapse, 
+			// since the synapse has not yet retracted its ack.
+			// Also there is the possibility, if really fast, that the line pull up block
+			// doesn't yet see that the input is valid, and starts pulling up.
+			// In any case, this delay is important.
 			sigbuf<Ny> req_bufs[Nx];
-			delay_fifo<10> more_delays[Nx];
+			delay_chain<N_dly> ack_delays[Nx];
 			(i:Nx:
-				more_delays[i].in = _out_reqsB[i];
-				more_delays[i].supply = supply;
+				ack_delays[i].in = _out_reqsB[i];
+				ack_delays[i].supply = supply;
 
 				// req_bufs[i].in = _out_reqsB[i];
-				req_bufs[i].in = more_delays[i].out;
+				req_bufs[i].in = ack_delays[i].out;
 				req_bufs[i].out[0] = _out_acksB[i]; // DANGER DANGER
 				req_bufs[i].supply = supply;
 
@@ -230,16 +236,12 @@ namespace tmpl {
 			)
 
 			// Line end pull UPs (triggered once synapse reqs removed)
-			delay_fifo<N_dly> pu_dlys[Nx];
 			OR2_X1 pu_ORs[Nx];
 			PULLUP_X4 pu[Nx]; // TODO probably replace this with variable strength PU
 			AND2_X1 pu_ANDs[Nx];
 			(i:Nx:
-				pu_dlys[i].in = d_dr_x.out[i];
-				pu_dlys[i].supply = supply;
-
 				pu_ORs[i].a = _out_acksB[i];
-				pu_ORs[i].b = pu_dlys[i].out;
+				pu_ORs[i].b = d_dr_x.out[i];
 				pu_ORs[i].vdd = supply.vdd;
 				pu_ORs[i].vss = supply.vss;
 
@@ -737,8 +739,8 @@ namespace tmpl {
 			// Create delay fifos to emulate the fact that the line pull downs
 			// are at the end of the line, and thus slow.
 			// Note that if N_dly = 0, delay fifo is just a pipe.
-			delay_fifo<N_dly> dly_x[Nx];
-			delay_fifo<N_dly> dly_y[Ny];	
+			delay_chain<N_dly> dly_x[Nx];
+			delay_chain<N_dly> dly_y[Ny];	
 			
 			// Create x line req pull downs
 			nrn_line_end_pull_down pd_x[Nx];