F11 Shortcut Key RGB / Composite for Tandy

* F11: CGA <-> HGC (PCXT) * RGB <-> Composite (Tandy)

PCXT.sv

@@ -1424,7 +1424,7 @@ module emu
 
     always_comb
     begin
-        if (swap_video)
+        if (swap_video & ~tandy_mode)
 
         HBlank_VGA = HBlank_del[color ? 12 : 13];
 
@@ -1571,14 +1571,14 @@ module emu
 	);
 
 
-    assign VGA_R_AUX  =  swap_video ? VGA_R_hgc  : VGA_R_cga;
-    assign VGA_G_AUX  =  swap_video ? VGA_G_hgc  : VGA_G_cga;
-    assign VGA_B_AUX  =  swap_video ? VGA_B_hgc  : VGA_B_cga;
-    assign VGA_HS =  swap_video ? VGA_HS_hgc : VGA_HS_cga;
-    assign VGA_VS =  swap_video ? VGA_VS_hgc : VGA_VS_cga;
-    assign VGA_DE =  swap_video ? VGA_DE_hgc : VGA_DE_cga;
-    assign gamma_bus =  swap_video ? gamma_bus_hgc : gamma_bus_cga;
-    assign CE_PIXEL  =  swap_video ? CE_PIXEL_hgc : CE_PIXEL_cga;
+    assign VGA_R_AUX  =  swap_video & ~tandy_mode ? VGA_R_hgc  : VGA_R_cga;
+    assign VGA_G_AUX  =  swap_video & ~tandy_mode ? VGA_G_hgc  : VGA_G_cga;
+    assign VGA_B_AUX  =  swap_video & ~tandy_mode ? VGA_B_hgc  : VGA_B_cga;
+    assign VGA_HS =  swap_video & ~tandy_mode ? VGA_HS_hgc : VGA_HS_cga;
+    assign VGA_VS =  swap_video & ~tandy_mode ? VGA_VS_hgc : VGA_VS_cga;
+    assign VGA_DE =  swap_video & ~tandy_mode ? VGA_DE_hgc : VGA_DE_cga;
+    assign gamma_bus =  swap_video & ~tandy_mode ? gamma_bus_hgc : gamma_bus_cga;
+    assign CE_PIXEL  =  swap_video & ~tandy_mode ? CE_PIXEL_hgc : CE_PIXEL_cga;
 
 
 
@@ -1674,7 +1674,7 @@ module emu
         .rotate     ( 2'd0  ),
         .toggle     ( 1'b0  ),
         .fast_scroll( 1'b0  ),
-        .border     ( swap_video ? 1'b0 : border_video_ff ),
+        .border     ( swap_video & ~tandy_mode ? 1'b0 : border_video_ff ),
 
         .vram_din   ( 8'h0  ),
         .vram_dout  (       ),

README.md

@@ -23,7 +23,8 @@ The [Graphics Gremlin project](https://github.com/schlae/graphics-gremlin) from
 * Support for IBM Tandy 1000
 * Support for IBM PCXT 5160 and clones (CGA graphics)
 * Main memory 640Kb + 384Kb UMB memory
-* Simultaneous video Hercules Graphics Card, F11 -> Swap Video Output (Only with PCXT model)
+* Simulated Composite Video, F11 -> Swap Video Output with RGB for Tandy model 
+* Simultaneous video Hercules Graphics Card, F11 -> Swap Video Output with CGA for PCXT model
 * Enable/Disable of CGA and Hercules I/O ports (Only with PCXT model)
 * 1st Graphics Card selection from System & BIOS (Only with PCXT model)
 * EMS memory up to 2Mb

SW/splash.txt

@@ -20,6 +20,6 @@
           (MicroCoreLabs)                            (TubeTime)    
                                                                    
                                                                    
-            F11: Swap Video Output HGC or CGA (Only PCXT model)    
+            F11: CGA <-> HGC (PCXT) * RGB <-> Composite (Tandy)    
             F12: Pause & Credits            Win + F12: Menu OSD    
                                                                    

rtl/KFPC-XT/HDL/KFPS2KB/HDL/KFPS2KB.sv

@@ -217,7 +217,7 @@ module KFPS2KB #(
     //
     always_ff @(posedge clock, posedge reset) begin
         if (reset) begin
-            swap_video  <= video_output;
+            swap_video  <= tandy_video ? 1'b0 : video_output;
             irq         <= 1'b0;
             keycode     <= 8'h00;
             break_flag  <= 1'b0;
@@ -252,8 +252,8 @@ module KFPS2KB #(
                 keycode     <= 8'h00;
                 break_flag  <= 1'b1;
             end
-            else if (register == 8'h78 & ~tandy_video) begin
-                // F11 -> Swap video (CGA <-> Hercules)
+            else if (register == 8'h78) begin
+                // F11: CGA <-> Hercules (PCXT), RGB <-> Composite (Tandy)
                 irq         <= 1'b0;
                 keycode     <= 8'h00;
                 break_flag  <= 1'b0;

rtl/KFPC-XT/HDL/Peripherals.sv

@@ -898,16 +898,16 @@ end
     wire[3:0] video_cga;
     wire video_hgc;
 
-    assign VGA_R = swap_video ? R_HGC : R_CGA;
-    assign VGA_G = swap_video ? G_HGC : G_CGA;
-    assign VGA_B = swap_video ? B_HGC : B_CGA;
-    assign VGA_HSYNC = swap_video ? HSYNC_HGC : HSYNC_CGA;
-    assign VGA_VSYNC = swap_video ? VSYNC_HGC : VSYNC_CGA;
+    assign VGA_R = swap_video & ~tandy_video ? R_HGC : R_CGA;
+    assign VGA_G = swap_video & ~tandy_video ? G_HGC : G_CGA;
+    assign VGA_B = swap_video & ~tandy_video ? B_HGC : B_CGA;
+    assign VGA_HSYNC = swap_video & ~tandy_video ? HSYNC_HGC : HSYNC_CGA;
+    assign VGA_VSYNC = swap_video & ~tandy_video ? VSYNC_HGC : VSYNC_CGA;
 
-    assign VGA_HBlank = swap_video ? HBLANK_HGC : HBLANK_CGA;
-    assign VGA_VBlank = swap_video ? VBLANK_HGC : VBLANK_CGA;
+    assign VGA_HBlank = swap_video & ~tandy_video ? HBLANK_HGC : HBLANK_CGA;
+    assign VGA_VBlank = swap_video & ~tandy_video ? VBLANK_HGC : VBLANK_CGA;
 
-    assign de_o = swap_video ? de_o_hgc : de_o_cga;
+    assign de_o = swap_video & ~tandy_video ? de_o_hgc : de_o_cga;
 
     wire HGC_VRAM_ENABLE;
     wire [18:0] HGC_VRAM_ADDR;
@@ -1002,7 +1002,7 @@ end
         .clkdiv(clkdiv),
         .video(video_cga),
         .hsync(VGA_HSYNC),
-        .composite(composite),
+        .composite(tandy_video ? swap_video ? ~composite : composite : composite),
         .red(R_CGA),
         .green(G_CGA),
         .blue(B_CGA)