From 488b41d0f0f3810ba65301624fa4a075c255c2c9 Mon Sep 17 00:00:00 2001
From: ZacJW <zac@zacjw.com>
Date: Sun, 14 Dec 2025 22:21:13 +0000
Subject: [PATCH] Started driver implementation

---
 .gitignore |   1 +
 Cargo.lock |  16 ++++++++
 Cargo.toml |   7 ++++
 src/lib.rs | 110 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 134 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 Cargo.lock
 create mode 100644 Cargo.toml
 create mode 100644 src/lib.rs

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..ea8c4bf
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+/target
diff --git a/Cargo.lock b/Cargo.lock
new file mode 100644
index 0000000..5f6495c
--- /dev/null
+++ b/Cargo.lock
@@ -0,0 +1,16 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "embedded-hal"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "361a90feb7004eca4019fb28352a9465666b24f840f5c3cddf0ff13920590b89"
+
+[[package]]
+name = "zel-gdeq031t10"
+version = "0.1.0"
+dependencies = [
+ "embedded-hal",
+]
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..f6f4648
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,7 @@
+[package]
+name = "zel-gdeq031t10"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+embedded-hal = "1.0.0"
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..b1ef66f
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,110 @@
+#![no_std]
+
+use embedded_hal::{
+    delay::DelayNs,
+    digital::{InputPin, OutputPin}, spi::{Operation, SpiDevice},
+};
+
+const EPD_WIDTH: u32 = 240;
+const EPD_HEIGHT: u32 = 320;
+const EPD_ARRAY: u32 = EPD_WIDTH * EPD_HEIGHT / 8;
+
+pub struct EPaperDisplay<BusyPin, ResetPin, DcPin, SpiDevice, Delay> {
+    busy: BusyPin,
+    reset: ResetPin,
+    dc: DcPin,
+    spi: SpiDevice,
+    delay: Delay,
+}
+
+pub enum InitError<ResetError, DcError, SpiError> {
+    ResetError(ResetError),
+    WriteError(WriteError<DcError, SpiError>),
+}
+
+pub enum WriteError<DcError, SpiError> {
+    DcError(DcError),
+    SpiError(SpiError),
+}
+
+impl<
+    BusyPin: InputPin,
+    ResetPin: OutputPin,
+    DcPin: OutputPin,
+    Spi: SpiDevice,
+    Delay: DelayNs,
+> EPaperDisplay<BusyPin, ResetPin, DcPin, Spi, Delay>
+{
+    pub fn new(
+        busy: BusyPin,
+        reset: ResetPin,
+        dc: DcPin,
+        spi: Spi,
+        delay: Delay,
+    ) -> Result<Self, InitError<ResetPin::Error, DcPin::Error, Spi::Error>> {
+        let mut display = Self {
+            busy,
+            reset,
+            dc,
+            spi,
+            delay,
+        };
+        display.init().map(|_| display)
+    }
+
+    fn write_command(&mut self, byte: u8) -> Result<(), WriteError<DcPin::Error, Spi::Error>> {
+        self.dc.set_low().map_err(WriteError::DcError)?;
+        self.spi.transaction(&mut [
+            Operation::DelayNs(60),
+            Operation::Write(&[byte]),
+            Operation::DelayNs(20),
+        ]).map_err(WriteError::SpiError)?;
+        self.delay.delay_ns(40);
+        Ok(())
+    }
+
+    fn write_data(&mut self, byte: u8) -> Result<(), WriteError<DcPin::Error, Spi::Error>> {
+        self.dc.set_high().map_err(WriteError::DcError)?;
+        self.spi.transaction(&mut [
+            Operation::DelayNs(60),
+            Operation::Write(&[byte]),
+            Operation::DelayNs(20),
+        ]).map_err(WriteError::SpiError)?;
+        self.delay.delay_ns(40);
+        Ok(())
+    }
+
+    fn wait_for_display(&mut self) {
+        while self.busy.is_low().expect("Failed to read busy pin") {}
+    }
+
+    fn init(&mut self) -> Result<(), InitError<ResetPin::Error, DcPin::Error, Spi::Error>> {
+        self.reset.set_low().map_err(InitError::ResetError)?;
+        self.delay.delay_ms(10);
+        self.reset.set_high().map_err(InitError::ResetError)?;
+        self.delay.delay_ms(10);
+
+        self.write_command(0x00).map_err(InitError::WriteError)?;
+        self.write_data(0x1f).map_err(InitError::WriteError)?;
+        self.write_command(0x04).map_err(InitError::WriteError)?;
+
+        self.wait_for_display();
+
+        Ok(())
+    }
+
+    fn clear_display(&mut self) {
+        self.write_command(0x10);
+        for _ in 0..EPD_ARRAY {
+            self.write_data(0xff);
+        }
+        self.write_command(0x13);
+        for _ in 0..EPD_ARRAY {
+            self.write_data(0xff);
+        }
+        self.write_command(0x12);
+
+        self.delay.delay_ms(1);
+        self.wait_for_display();
+    }
+}