add support for ZXKIT1 vga converter

When ZXKIT1 setting enabled in menu:
- Hsync on EGA header acts as Csync
- Vsync on EGA header acts as 14MHz out

cpld/rtl/magic.sv

@@ -37,7 +37,8 @@ module magic(
     output reg covox_en,
     output reg soundrive_en,
     output reg sd_indication_en,
-    output reg bright_boost
+    output reg bright_boost,
+    output reg zxkit1
 );
 
 localparam magic_on_start = 1'b1;
@@ -132,6 +133,7 @@ always @(posedge clk28 or negedge rst_n) begin
             bright_boost <= 1'b0;
         `endif
         autoturbo_en <= 1'b0;
+        zxkit1 <= 1'b0;
     end
     else if (config_cs && bus.wr) case (bus.a[15:8])
         8'h01: {rom_wren, magic_reboot, magic_beeper} <= bus.d[2:0];
@@ -148,6 +150,7 @@ always @(posedge clk28 or negedge rst_n) begin
         8'h0C: sd_indication_en <= bus.d[0];
         8'h0D: bright_boost <= bus.d[0];
         8'h0E: autoturbo_en <= bus.d[0];
+        8'h0F: zxkit1 <= bus.d[0];
     endcase
 end
 

cpld/rtl/top.sv

@@ -92,6 +92,7 @@ wire ay_wait;
 wire div_wait;
 wire sd_indication;
 wire bright_boost;
+wire zxkit1;
 
 
 /* CPU BUS */
@@ -156,6 +157,9 @@ wire [8:0] vc, hc;
 wire [4:0] blink_cnt;
 wire blink, even_line;
 wire clk14, clk7, clk35, ck14, ck7, ck35;
+wire vsync0, hsync0;
+assign vsync = zxkit1? clk14 : vsync0;
+assign hsync = zxkit1? csync : hsync0;
 screen screen0(
     .rst_n(usrrst_n),
     .clk28(clk28),
@@ -168,8 +172,8 @@ screen screen0(
     .g(g0),
     .b(b0),
     .csync(csync),
-    .vsync(vsync),
-    .hsync(hsync),
+    .vsync(vsync0),
+    .hsync(hsync0),
 
     .fetch_allow((!up_write_req && !bus.mreq) || bus.rfsh || (clkwait && turbo == TURBO_NONE)),
     .fetch(screen_fetch),
@@ -371,7 +375,8 @@ magic magic0(
     .covox_en(covox_en),
     .soundrive_en(soundrive_en),
     .sd_indication_en(sd_indication_en),
-    .bright_boost(bright_boost)
+    .bright_boost(bright_boost),
+    .zxkit1(zxkit1)
 );
 
 

rom_src/config.asm

@@ -44,6 +44,7 @@ dac        DB 3
 sdind      DB 1
 bright     DB BRIGHT_DEFAULT
 autoturbo  DB 0
+zxkit1     DB 0
 ENDIF
     ENDS
 

rom_src/menu_structure.asm

@@ -64,6 +64,7 @@ menuadv: MENU_DEF 22
     MENUENTRY_T str_sd_indication menu_sdind_value_cb     menu_sdind_cb
     MENUENTRY_T str_bright_boost  menu_bright_value_cb    menu_bright_cb
     MENUENTRY_T str_autoturbo     menu_autoturbo_value_cb menu_autoturbo_cb
+    MENUENTRY_T str_zxkit1        menu_zxkit1_value_cb    menu_zxkit1_cb
     MENUENTRY_T str_save_settings menu_cfgsave_value_cb   menu_cfgsave_cb
     MENUENTRY_T str_back          0                       menu_back_cb
     MENUENTRY_T 0
@@ -224,6 +225,14 @@ menu_autoturbo_value_cb:
     DW str_off_short_end-2
     DW str_on_short_end-2
 
+menu_zxkit1_value_cb:
+    ld ix, .values_table
+    ld a, (cfg.zxkit1)
+    jp menu_value_get
+.values_table:
+    DW str_off_short_end-2
+    DW str_on_short_end-2
+
 menu_cfgsave_value_cb:
     ld ix, .values_table
     ld a, (var_flash_error)
@@ -403,6 +412,15 @@ menu_autoturbo_cb:
     out (c), a
     ret
 
+menu_zxkit1_cb:
+    ld a, (cfg.zxkit1)
+    ld c, 1
+    call menu_handle_press
+    ld (cfg.zxkit1), a
+    ld bc, #0fff
+    out (c), a
+    ret
+
 menu_cfgsave_cb:
     bit 4, d                ; action?
     ret z

rom_src/strings.asm

@@ -138,6 +138,9 @@ str_bright_boost_end:
 str_autoturbo: DB "Auto CPU freq",0
 str_autoturbo_end:
 
+str_zxkit1: DB "ZXKit1",0
+str_zxkit1_end:
+
 str_save_settings: DB "Save settings",0
 str_save_settings_end: