1 files changed, 13 insertions, 1 deletions
diff --git a/src/peripherals/gpio.spec.ts b/src/peripherals/gpio.spec.ts
index 692deaa..31963a9 100644
--- a/src/peripherals/gpio.spec.ts
+++ b/src/peripherals/gpio.spec.ts
@@ -1,5 +1,5 @@
 import { CPU } from '../cpu/cpu';
-import { AVRIOPort, portBConfig, PinState, portDConfig } from './gpio';
+import { AVRIOPort, portBConfig, PinState, portDConfig, PinOverrideMode } from './gpio';
 
 // CPU registers
 const SREG = 95;
@@ -76,6 +76,18 @@ describe('GPIO', () => {
     expect(cpu.data[PINB]).toEqual(0x4); // PINB should return port value
   });
 
+  it('should update the PIN register on output compare (OCR) match (issue #102)', () => {
+    const cpu = new CPU(new Uint16Array(1024));
+    const port = new AVRIOPort(cpu, portBConfig);
+    cpu.writeData(DDRB, 1 << 1);
+    cpu.gpioTimerHooks[PORTB](1, PinOverrideMode.Set, PORTB);
+    expect(port.pinState(1)).toBe(PinState.High);
+    expect(cpu.data[PINB]).toBe(1 << 1);
+    cpu.gpioTimerHooks[PORTB](1, PinOverrideMode.Clear, PORTB);
+    expect(port.pinState(1)).toBe(PinState.Low);
+    expect(cpu.data[PINB]).toBe(0);
+  });
+
   describe('removeListener', () => {
     it('should remove the given listener', () => {
       const cpu = new CPU(new Uint16Array(1024));