From 0d0f90e91d25e5ac02c1f48f8796a4d19019c7e1 Mon Sep 17 00:00:00 2001
From: Savanni D'Gerinel <savanni@luminescent-dreams.com>
Date: Thu, 14 Jul 2022 19:11:23 -0400
Subject: [PATCH] Create the initial display application

---
 display-i2c/main.c | 27 +++++++++++++++++++++++++++
 flake.nix          | 23 ++++++++++++++++++++++-
 2 files changed, 49 insertions(+), 1 deletion(-)
 create mode 100644 display-i2c/main.c

diff --git a/display-i2c/main.c b/display-i2c/main.c
new file mode 100644
index 0000000..e02ec82
--- /dev/null
+++ b/display-i2c/main.c
@@ -0,0 +1,27 @@
+#include <display.h>
+#include <stdio.h>
+
+int main(void) {
+    display_t display = {
+        .reg = {
+            .output         = { .ddr = &DDRB, .port = &PORTB, .pin = &PINB, .addr = 3 },
+            .shift_clock    = { .ddr = &DDRB, .port = &PORTB, .pin = &PINB, .addr = 2 },
+            .latch_clock    = { .ddr = &DDRB, .port = &PORTB, .pin = &PINB, .addr = 0 },
+        },
+    };
+
+    int count = 0;
+    while (1) {
+        display_init(&display);
+
+        char msg[15];
+        snprintf(msg, 15, "[%d]", count);
+        display_clear(&display);
+        display_write_message(&display, msg);
+        _delay_ms(1000);
+
+        count++;
+    }
+
+    return 0;
+}
diff --git a/flake.nix b/flake.nix
index 12ab68c..87a3ac3 100644
--- a/flake.nix
+++ b/flake.nix
@@ -90,6 +90,7 @@
             (packages."x86_64-linux"."radio-rx" { gcc = "${avr.gcc}/bin/avr-gcc"; cflags = mcu_cflags atmega32u4; })
             (packages."x86_64-linux"."lantern" { gcc = "${avr.gcc}/bin/avr-gcc"; cflags = mcu_cflags atmega32u4; avr = true; })
             (packages."x86_64-linux"."lantern-controller" { gcc = "${avr.gcc}/bin/avr-gcc"; cflags = mcu_cflags atmega32u4; avr = true; })
+            (packages."x86_64-linux"."display-i2c" { gcc = "${avr.gcc}/bin/avr-gcc"; cflags = mcu_cflags atmega32u4; avr = true; })
           ];
         };
 
@@ -236,7 +237,7 @@
       let
         pkgs = import nixpkgs { system = "x86_64-linux"; };
         avr = pkgs.pkgsCross.avr.buildPackages;
-      in packages."x86_64-linux"."lantern" { gcc = "${avr.gcc}/bin/avr-gcc"; cflags = mcu_cflags atmega32u4; };
+      in packages."x86_64-linux"."lantern" { gcc = "${avr.gcc}/bin/avr-gcc"; cflags = mcu_cflags atmega32u4; avr = true; };
       packages."x86_64-linux"."lantern" =
         { gcc, cflags, avr }:
         let
@@ -284,6 +285,26 @@
           ];
         };
 
+      packages."x86_64-linux"."display-i2c" =
+        { gcc, cflags, avr }:
+        let
+          pkgs = import nixpkgs { system = "x86_64-linux"; };
+        in mkProgram {
+          pkgs = pkgs;
+          gcc = gcc;
+          cflags = cflags;
+          pname = "display-i2c";
+          psrc = ./display-i2c;
+          inherit avr;
+
+          pbuildInputs = [
+            (packages."x86_64-linux"."dio" { inherit gcc cflags; })
+            (packages."x86_64-linux"."spi" { inherit gcc cflags; })
+            (packages."x86_64-linux"."shift-register" { inherit gcc cflags; })
+            (packages."x86_64-linux"."display" { inherit gcc cflags; })
+          ];
+        };
+
       devShell."x86_64-linux" =
         let
           pkgs = import nixpkgs { system = "x86_64-linux"; };