diff --git a/rust/pm-kit/src/main.rs b/rust/pm-kit/src/main.rs
index 9d4393e..bda949f 100644
--- a/rust/pm-kit/src/main.rs
+++ b/rust/pm-kit/src/main.rs
@@ -17,7 +17,7 @@ use embedded_graphics::{
 use embedded_hal::delay::DelayNs;
 use embedded_hal::digital::OutputPin;
 use embedded_hal_bus::spi::ExclusiveDevice;
-use mipidsi::interface::SpiInterface;
+use mipidsi::interface::{Interface, SpiInterface};
 use mipidsi::models::ST7796;
 use mipidsi::options::{ColorInversion, ColorOrder, Orientation};
 use mipidsi::Builder;
@@ -85,6 +85,26 @@ fn main() -> ! {
         .init(&mut timer)
         .unwrap();
 
+    // ST7796-specific setup that mipidsi's ST7789-based init omits. The critical one is 0xB6
+    // (Display Function Control → 480 driving lines); without it the panel only scans part of
+    // the screen. Sequence + values from the working CircuitPython firmware (st7796_init).
+    {
+        let di = unsafe { display.dcs() };
+        di.send_command(0xF0, &[0xC3]).unwrap(); // unlock extension command set
+        di.send_command(0xF0, &[0x96]).unwrap();
+        di.send_command(0xB4, &[0x01]).unwrap(); // 1-dot inversion
+        di.send_command(0xB6, &[0x80, 0x02, 0x3B]).unwrap(); // display function control: 480 lines
+        di.send_command(0xE8, &[0x40, 0x8A, 0x00, 0x00, 0x29, 0x19, 0xA5, 0x33]).unwrap();
+        di.send_command(0xC1, &[0x06]).unwrap();
+        di.send_command(0xC2, &[0xA7]).unwrap();
+        di.send_command(0xC5, &[0x18]).unwrap();
+        di.send_command(0xE0, &[0xF0, 0x09, 0x0B, 0x06, 0x04, 0x15, 0x2F, 0x54, 0x42, 0x3C, 0x17, 0x14, 0x18, 0x1B]).unwrap();
+        di.send_command(0xE1, &[0xE0, 0x09, 0x0B, 0x06, 0x04, 0x03, 0x2B, 0x43, 0x42, 0x3B, 0x16, 0x14, 0x17, 0x1B]).unwrap();
+        di.send_command(0xF0, &[0x3C]).unwrap(); // lock
+        di.send_command(0xF0, &[0x69]).unwrap();
+    }
+    timer.delay_ms(120);
+
     let w = WIDTH as i32;
     let h = HEIGHT as i32;
     let m = 36; // marker size