(fix): Attempted to implement APB Manager (4/19)

rtl/apb/devices/APBManager.sv

@@ -0,0 +1,67 @@
+// Used GenericBusManager.sv as template for outline
+
+/**
+  @brief Manager that uses the GenericBus protocol directly as the transmission
+    protocol
+
+  @input device     managing device
+  @input bus        bus to managed
+ */
+
+module APBManager (
+    APBCommon_if bus,
+    APBCommon_if bridge
+);
+  always_comb begin
+    bridge.rData = bus.rData;
+    bridge.subError <= bus.subError;
+  end
+
+  always_ff @(posedge bridge.clk, negedge bridge.nReset) begin
+    if (!bridge.nReset) begin
+      bus.write <= 0;
+      bus.addr <= 0;
+      bus.wData <= 0;
+      bus.prot <= 0;
+      bus.enable <= 0;
+
+    /** 
+    - Alert subordinate that we're writing to it
+    - Set up write and enable
+    - Check ready signal 
+    **/    
+    end else if (!bus.ready || !bus.enable) begin // wake up bus
+      bus.sel[bridge.sel] <= 1;
+    end else if (bus.ready && !bus.enable) begin
+      bus.enable <= 1;
+      bus.write <= bridge.write;
+      bus.addr <= bridge.addr;
+      bus.prot <= bridge.prot;
+      bus.wData <= bridge.wData;
+    end else if (bus.subError) begin
+      bus.enable = 0;
+    end
+  end
+endmodule
+
+/**
+APB Interface Signals
+NEED TO GIVE DIRECTION -> Logic just says we care about variable
+
+  input [AddrWidth-1:0] addr;           // Address bus
+  input [3:0] prot;                     // protected piece of mail 
+  output [PrphNum-1:0] selectors;       // sending a bit on the selector on bus where peripherals live; 
+  think as array of subordinates live (bit will let subordinate to get ready) -> Read APB Spec for more detail
+                                        // To know where each subordinate lives, address is sent to decoder & 
+                                        decoder tells us which subordinate we need to talk to in array
+  output enable;                        // Bit that tells us if person is getting multiple "packages"
+  output write;
+  inout [DataWidth - 1:0] wData;        // 1 of 2 Data Buses
+  inout(?) [DataWidth/8 - 1:0] strb;    // Ignore bc AHB ignores strobe 
+  input ready;                        
+  inout [DataWidth - 1:0] rData;        // 2 of 2 Data buses
+  input subError;
+
+
+My APB will support up to 8 subordinates
+**/

rtl/apb/interfaces/APBCommon_if.sv

@@ -54,6 +54,18 @@ interface APBCommon_if #(
       output write,
       output wData
   );
+
+    modport manager(
+    input addr,          
+    input prot,                     
+    output selectors,       
+    output enable,                        
+    inout wData,       
+    inout strb,   
+    input ready,                       
+    inout rData,       
+    input subError
+  );
 
 endinterface