Shave a master clock cycle off the SPI transfer by initiating frame start on...

Shave a master clock cycle off the SPI transfer by initiating frame start on transition from idle state

spi_master.v

@@ -48,8 +48,14 @@ module spi_master_interface(
 					transaction_complete <= 0;
 					state_iteration <= 0;
 					if (cycle_start_reg) begin
+						// Set up transfer
 						rx_data <= 0;
 						data_shift_out <= tx_data_reg;
+
+						// Drive frame start
+						spi_clock <= 1'b1;
+						spi_ss_n <= 1'b0;
+
 						transfer_state <= 1;
 					end else begin
 						if (!hold_ss_active_reg) begin
@@ -59,21 +65,14 @@ module spi_master_interface(
 					end
 				end
 				1: begin
-					// Drive frame start
-					spi_clock <= 1'b1;
-					spi_ss_n <= 1'b0;
-					state_iteration <= 0;
-					transfer_state <= 2;
-				end
-				2: begin
 					// Shift out TX byte / toggle clock
 					spi_clock <= 1'b0;
 					spi_ss_n <= 1'b0;
 					spi_mosi <= data_shift_out[7];
 					data_shift_out <= data_shift_out << 1;
-					transfer_state <= 3;
+					transfer_state <= 2;
 				end
-				3: begin
+				2: begin
 					// Shift in RX byte / toggle clock
 					spi_clock <= 1'b1;
 					spi_ss_n <= 1'b0;
@@ -86,12 +85,12 @@ module spi_master_interface(
 							ss_state_at_idle <= 1'b1;
 						end
 						transaction_complete <= 1;
-						transfer_state <= 4;
+						transfer_state <= 3;
 					end else begin
-						transfer_state <= 2;
+						transfer_state <= 1;
 					end
 				end
-				4: begin
+				3: begin
 					// Wait for host to deassert transaction request
 					if (!cycle_start_reg) begin
 						transaction_complete <= 0;