From: Florent Kermarrec <florent@enjoy-digital.fr>
Date: Fri, 8 May 2020 11:17:59 +0000 (+0200)
Subject: cores/led: add LedChaser (now that LiteX is running on FPGA mining boards let's use... 
X-Git-Tag: 24jan2021_ls180~370
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=05869beb722e6862118d5879fde57e90a8dc04e2;p=litex.git

cores/led: add LedChaser (now that LiteX is running on FPGA mining boards let's use fancy led blinks :))
---

diff --git a/litex/soc/cores/led.py b/litex/soc/cores/led.py
new file mode 100644
index 00000000..727000e0
--- /dev/null
+++ b/litex/soc/cores/led.py
@@ -0,0 +1,35 @@
+# This file is Copyright (c) 2020 Florent Kermarrec <florent@enjoy-digital.fr>
+# License: BSD
+
+from migen import *
+from migen.genlib.misc import WaitTimer
+
+from litex.soc.interconnect.csr import *
+
+# Led Chaser ---------------------------------------------------------------------------------------
+
+class LedChaser(Module, AutoCSR):
+    def __init__(self, pads, sys_clk_freq, period=1e0):
+        self.control  = CSRStorage(fields=[
+            CSRField("mode", size=2, values=[
+                ("``0b0``", "Chaser mode."),
+                ("``0b1``", "CPU mode."),
+            ])
+        ])
+        self.value = CSRStorage(len(pads), description="Control value when in CPU mode.")
+
+        # # #
+
+        n      = len(pads)
+        chaser = Signal(n)
+        timer  = WaitTimer(int(period*sys_clk_freq/(2*n)))
+        self.submodules += timer
+        self.comb += timer.wait.eq(~timer.done)
+        self.sync += If(timer.done, chaser.eq(Cat(~chaser[-1], chaser)))
+        self.comb += [
+            If(self.control.fields.mode,
+                pads.eq(self.value.storage)
+            ).Else(
+                pads.eq(chaser)
+            )
+        ]