unset the interrupt when the divider is on after the first interrupt …

…pulse

src/test.py

@@ -51,7 +51,6 @@ async def test_one_shot(dut):
 
 @cocotb.test()
 async def repeating_no_divider(dut):
-
     dut._log.info("start")
     clock = Clock(dut.clk, 10, units="us")
     cocotb.start_soon(clock.start())
@@ -84,5 +83,35 @@ async def repeating_no_divider(dut):
     dut.uio_in.value = 0x0  # unset we so we no longer configure registers.
     await ClockCycles(dut.clk, 10)
     dut._log.info("checking that interrupt is high")
-    assert dut.uo_out.value == 0b01000000
+    assert dut.uo_out.value == 0b1000_0000
     await ClockCycles(dut.clk, 10)
+
+
+@cocotb.test()
+async def oneshot_divided(dut):
+    dut._log.info("start")
+    clock = Clock(dut.clk, 10, units="us")
+    cocotb.start_soon(clock.start())
+
+    # reset
+    dut._log.info("reset")
+    dut.rst_n.value = 0
+    await ClockCycles(dut.clk, 2)
+
+    dut.rst_n.value = 1
+
+    dut.uio_in.value = 0x80  # set we high and config_address to 0b00
+    dut.ui_in.value = 0x80  # set divider to on, repeating off
+    await ClockCycles(dut.clk, 2)
+
+    dut.uio_in.value = 0xC0  # set we high and config_address to 0b01
+    dut.ui_in.value = 0x00  # should not set temp_counter
+    await ClockCycles(dut.clk, 2)
+
+    dut.uio_in.value = 0xA0  # set we high and config_address to 0b10
+    dut.ui_in.value = 0x01  # wait one cycle, with a divider will be 10 cycles
+    await ClockCycles(dut.clk, 14)
+    dut.uio_in.value = 0x0  # unset we so we no longer configure registers.
+
+    dut._log.info("checking that interrupt is high")
+    assert dut.uo_out.value == 0b1100_1000

src/tt_um_minipit_stevej.v

@@ -36,7 +36,7 @@ module tt_um_minipit_stevej (
     reg [15:0] current_count;
 
     // A counter to use when the divider is enabled
-    reg [8:0] divider_count;
+    reg [7:0] divider_count;
 
     // uo_out is always a status byte
     assign uo_out = {divider_on, counter_set, 1'b0, 1'b0, interrupting, 1'b0, 1'b0, 1'b0};
@@ -88,13 +88,17 @@ module tt_um_minipit_stevej (
                 `endif
                 current_count <= current_count + 1;
             end
-
+            // todo: unset the interrupt
             if (counter_set && (current_count == counter)) begin
                 // pull interrupt line high for one clock cycle
                 interrupting <= 1;
                 if (repeating) begin
                     current_count <= 0;
                 end
+                // on a rollover of divider_count, reset the interrupt
+                if (divider_on && (divider_count > 0)) begin
+                    interrupting <= 0; // this is hokey.
+                end
             end else begin
                 interrupting <= 0;
             end