diff --git a/src/tester_io.rs b/src/tester_io.rs
index aa58d71d8e99..8cd62150908d 100644
--- a/src/tester_io.rs
+++ b/src/tester_io.rs
@@ -26,8 +26,8 @@ pub enum TesterStatus {
 
 pub struct TesterIo {
     peripheral: dp::PeripheralHandle,
-    valve_states: u8,
     tester_status: TesterStatus,
+    valve_states: [bool; 8],
 }
 
 impl TesterIo {
@@ -76,20 +76,23 @@ impl TesterIo {
 
         Self {
             peripheral: handle,
-            valve_states: 0,
+            valve_states: [false; 8],
             tester_status: TesterStatus::Ready,
         }
     }
 
-    pub fn valve_states(&self) -> u8 {
-        self.valve_states
+    pub fn valve_states(&self) -> &[bool] {
+        &self.valve_states
     }
 
     pub fn update(&mut self, dp_master: &mut dp::DpMaster, events: &dp::DpEvents) {
         let peripheral = dp_master.get_mut(self.peripheral);
         if peripheral.is_running() && events.cycle_completed {
             // Die 8 Eingänge der ET200B werden auf die 8 Bits für die Ventile gemapped.
-            self.valve_states = peripheral.pi_i()[0];
+            let pi_i = peripheral.pi_i();
+            for (i, valve) in self.valve_states.iter_mut().enumerate() {
+                *valve =  pi_i[i / 8] & (1 << (i % 8)) != 0;
+            }
 
             // Ausgänge:
             // - Bit 0: Leuchtmelder "Test-Station bereit"
diff --git a/src/valve_terminal.rs b/src/valve_terminal.rs
index b1b90db5a7ec..9213f88454aa 100644
--- a/src/valve_terminal.rs
+++ b/src/valve_terminal.rs
@@ -13,7 +13,7 @@ const VALVE_TERMINAL_IDENT_NUMBER: u16 = 0x0a35;
 pub struct ValveTerminal {
     peripheral: dp::PeripheralHandle,
     address: profirust::Address,
-    valve_states: u8,
+    valve_states: [bool; 8],
 }
 
 impl ValveTerminal {
@@ -68,7 +68,7 @@ impl ValveTerminal {
         Self {
             peripheral: handle,
             address: default_address,
-            valve_states: 0,
+            valve_states: [false; 8],
         }
     }
 
@@ -89,18 +89,27 @@ impl ValveTerminal {
             let peripheral = dp_master.get_mut(self.peripheral);
             peripheral.reset_address(address);
             peripheral.pi_q_mut().fill(0u8);
-            self.valve_states = 0;
+            self.valve_states = [false; 8];
         }
     }
 
-    pub fn update_valve_states(&mut self, valve_states: u8) {
-        self.valve_states = valve_states;
+    pub fn update_valve_states(&mut self, valve_states: &[bool]) {
+        if self.valve_states != valve_states {
+            self.valve_states.copy_from_slice(valve_states);
+            log::info!("Ventile: {:?}", valve_states);
+        }
     }
 
     pub fn update(&mut self, dp_master: &mut dp::DpMaster, events: &dp::DpEvents) {
         let peripheral = dp_master.get_mut(self.peripheral);
         if peripheral.is_running() && events.cycle_completed {
-            peripheral.pi_q_mut()[0] = self.valve_states;
+            let pi_q = peripheral.pi_q_mut();
+            pi_q.fill(0);
+            for (i, valve) in self.valve_states.iter().enumerate() {
+                let bit_index = i * 2;
+                let bit_value = if *valve { 1 } else { 0 };
+                pi_q[bit_index / 8] |= bit_value << (bit_index % 8);
+            }
         }
     }
 }