Add mouse events in FIFO instead of absolute coordinates

doc/memory_map.rst

@@ -19,7 +19,7 @@ LED                 BASE_IO + 4
 UART                BASE_IO + 8
 SD_CARD             BASE_IO + 16
 KEYBOARD            BASE_IO + 24
-MOUSE               BASE_IO + 24
 GRAPHITE            BASE_IO + 32
 CONFIG              BASE_IO + 36
+MOUSE               BASE_IO + 40
 ==================  ===============

doc/mouse.rst

@@ -9,22 +9,37 @@ Registers
 =============== =============
 Register        Address
 =============== =============
-MOUSE           BASE_IO + 24
+MOUSE_STATUS    BASE_IO + 40
+MOUSE_DATA      BASE_IO + 44
 =============== =============
 
-MOUSE
-^^^^^
+MOUSE_STATUS
+^^^^^^^^^^^^
+
+Read:
+
+===== ============================
+Field Description
+===== ============================
+[28]  Mouse event available? 
+===== ============================
+
+Write: -
+
+MOUSE_DATA
+^^^^^^^^^^
 
 Read:
 
 ======= ============================
 Field   Description
 ======= ============================
-[9:0]   X position
-[21:12] Y position
-[24]    Left button
-[25]    Middle button
-[26]    Right button
+[7:0]   Delta Z
+[15:8]  Delta Y
+[23:16] Delta X
+[24]    Left button pressed?
+[25]    Right button pressed?
+[26]    Middle button pressed?
 ======= ============================
 
 Write: -

soc/rtl/ps2mouse.v

@@ -27,22 +27,15 @@ CONNECTION WITH THE DEALINGS IN OR USE OR PERFORMANCE OF THE SOFTWARE.*/
 
 module ps2mouse
 #(
-  parameter c_x_bits = 11,   // >= 8
-  parameter c_y_bits = 11,   // >= 8
-  parameter c_y_neg  = 0,
-  parameter c_z_bits = 11,   // >= 4
-  parameter c_z_ena  = 1,    // 1:yes wheel, 0:not wheel
-  parameter c_hotplug = 1
+  parameter c_z_ena  = 1    // 1:yes wheel, 0:not wheel
 )
 (
-  input clk, clk_ena,
+  input clk,
   input ps2m_reset,
   inout ps2m_clk, ps2m_dat,
-  output reg update,
-  output reg [c_x_bits-1:0] x,
-  output reg [c_y_bits-1:0] y,
-  output reg [c_z_bits-1:0] z,
-  output reg [2:0] btn
+  input done,   // "word has been read"
+  output rdy,   // "word is available"
+  output [26:0] data  
 );
   reg [2:0] sent;
   localparam c_rx_bits = c_z_ena ? 42 : 31;
@@ -51,11 +44,12 @@ module ps2mouse
   reg [14:0] count;
   reg [5:0] filter;
   reg req;
-  wire shift, endbit, endcount, done, run;
+  wire shift, endbit, endcount, donereq, run;
   wire [8:0] cmd;  //including odd tx parity bit
-  wire [c_x_bits-1:0] dx;
-  wire [c_y_bits-1:0] dy;
-  wire [c_z_bits-1:0] dz;
+  wire [7:0] dx;
+  wire [7:0] dy;
+  wire [7:0] dz;
+  wire [2:0] btn;  
 
 // 322222222221111111111 (scroll mouse z and rx parity p ignored)
 // 0987654321098765432109876543210   X, Y = overflow
@@ -87,32 +81,34 @@ module ps2mouse
   // first bit that enters rx at MSB is 1 and it is shifted to the right
   // when this bit reaches the position in rx, it indicates end of transmission
   assign endbit = run ? ~rx[0] : ~rx[$bits(rx)-21];
-  assign done = endbit & endcount & ~req;
+  assign donereq = endbit & endcount & ~req;
   assign dx = {{($bits(dx)-8){rx[5]}}, rx[7] ? 8'b0 : rx[19:12]};  //sign+overfl
   assign dy = {{($bits(dy)-8){rx[6]}}, rx[8] ? 8'b0 : rx[30:23]};  //sign+overfl
   generate
     if(c_z_ena)
       assign dz = {{($bits(dz)-3){rx[37]}}, rx[37:34]};  //sign,wheel
   endgenerate
-//  assign out = {run,  // full debug
-//    run ? {rx[25:0], endbit} : {rx[30:10], endbit, sent, tx[0], ~req}};
-//  assign out = {run,  // debug then normal
-//    run ? {btns, 2'b0, y, 2'b0, x} : {rx[30:10], sent, endbit, tx[0], ~req}};
+  assign btn = rx[3:1];
   assign ps2m_clk = req ? 1'b0 : 1'bz;  //bidir clk/request
   assign ps2m_dat = ~tx[0] ? 1'b0 : 1'bz;  //bidir data
 
+  reg [3:0] inptr, outptr;
+  reg [26:0] fifo [15:0];  // 16 word buffer
+
+  assign data = fifo[outptr];
+  assign rdy = ~(inptr == outptr);
+
   always @ (posedge clk) begin
     filter <= {filter[$bits(filter)-2:0], ps2m_clk};
     count <= (ps2m_reset | shift | endcount) ? 0 : count+1;
     req <= ~ps2m_reset & ~run & (req ^ endcount);
-    sent <= ps2m_reset ? 0 : (done & ~run) ? sent+1 : sent;
+    sent <= ps2m_reset ? 0 : (donereq & ~run) ? sent+1 : sent;
     tx <= (ps2m_reset | run) ? {$bits(tx){1'b1}} : req ? {cmd, 1'b0} : shift ? {1'b1, tx[$bits(tx)-1:1]} : tx;
-    rx <= (ps2m_reset | done) ? {$bits(rx){1'b1}} : (shift & ~endbit) ? {ps2m_dat, rx[$bits(rx)-1:1]} : rx;
-    x <= ~run ? 0 : done ? x + dx : x;
-    y <= ~run ? 0 : done ? (c_y_neg ? y + dy : y - dy) : y;
-    z <= ~run ? 0 : done ? z + dz : z;
-    btn <= ~run ? 0 : done ? rx[3:1] : btn;
-    update <= done;
+    rx <= (ps2m_reset | donereq) ? {$bits(rx){1'b1}} : (shift & ~endbit) ? {ps2m_dat, rx[$bits(rx)-1:1]} : rx;
+
+    outptr <= ps2m_reset ? 0 : rdy & done ? outptr+1 : outptr;
+    inptr <= ps2m_reset ? 0 : run & donereq ? inptr+1 : inptr;
+    if (donereq) fifo[inptr] <= {btn, dx, dy, dz};
   end
 
 endmodule

soc/rtl/soc_top.sv

@@ -144,7 +144,9 @@ module soc_top #(
     logic [7:0] dataKbd;
     logic rdyKbd;
     logic doneKbd;
-    logic [27:0] dataMs;
+    logic rdyMs;
+    logic doneMs;
+    logic [26:0] dataMs;
     logic limit;  // of cnt0
 
     logic [16:0] cnt0 = 0;
@@ -302,18 +304,13 @@ module soc_top #(
     .viddata(inbusvid), .de(de), .RGB(RGB), .hsync(vga_hsync), .vsync(vga_vsync));
     ps2kbd ps2kbd(.clk(clk_cpu), .rst(rst_n), .done(doneKbd), .rdy(rdyKbd), .shift(),
     .data(dataKbd), .PS2C(ps2clka_i), .PS2D(ps2data_i));
-    logic [2:0] mousebtn;
     ps2mouse
-    #(.c_x_bits(10), .c_y_bits(10), .c_y_neg(1), .c_z_ena(0), .c_hotplug(1))
+    #(.c_z_ena(1))
     ps2mouse
     (
-    .clk(clk_cpu), .clk_ena(1'b1), .ps2m_reset(~rst_n), .ps2m_clk(ps2clkb_io), .ps2m_dat(ps2datb_io),
-    .x(dataMs[9:0]), .y(dataMs[21:12]), .btn(mousebtn)
+    .clk(clk_cpu), .ps2m_reset(~rst_n), .ps2m_clk(ps2clkb_io), .ps2m_dat(ps2datb_io),
+    .done(doneMs), .rdy(rdyMs), .data(dataMs)   
     );
-    assign dataMs[24] = mousebtn[1]; // left
-    assign dataMs[25] = mousebtn[2]; // middle
-    assign dataMs[26] = mousebtn[0]; // right
-    assign dataMs[27] = 1'b1;
 
     // Graphite
     logic           graphite_cmd_axis_tvalid;
@@ -364,10 +361,12 @@ module soc_top #(
         (iowadr == 3) ? {30'b0, rdyTx, rdyRx} :
         (iowadr == 4) ? spiRx :
         (iowadr == 5) ? {31'b0, spiRdy} :
-        (iowadr == 6) ? {3'b0, rdyKbd, dataMs} :
+        (iowadr == 6) ? {3'b0, rdyKbd, 28'd0} :
         (iowadr == 7) ? {24'b0, dataKbd} :
         (iowadr == 8) ? {31'b0, graphite_cmd_axis_tready} :
-        (iowadr == 9) ? {16'(H_RES), 16'(V_RES)} : 32'd0);
+        (iowadr == 9) ? {16'(H_RES), 16'(V_RES)} :
+        (iowadr == 10) ? {3'b0, rdyMs, 28'd0} :
+        (iowadr == 11) ? {5'b0, dataMs} : 32'd0);
 
     assign dataTx = outbus[7:0];
     assign startTx = wr & ioenb & (iowadr == 2);
@@ -383,6 +382,12 @@ module soc_top #(
             doneKbd <= 1'b1;
     end
 
+    always @(posedge clk_cpu) begin
+        doneMs <= 1'b0;
+        if (rd & ioenb & (iowadr == 11))
+            doneMs <= 1'b1;
+    end
+
     // Auto reset and counter
     always_ff @(posedge clk_cpu) begin
     `ifdef SYNTHESIS