From c66353b055d6d631ddc6041e2dc378db85c1f4ad Mon Sep 17 00:00:00 2001
From: Robert Jensen <jensen.robert@gmail.com>
Date: Fri, 26 Jun 2026 11:10:48 +0200
Subject: [PATCH] Driver for Geopal GPU45

---
 PyExpLabSys/drivers/geopal_gpu45.py | 49 +++++++++++++++++++++++++++++
 1 file changed, 49 insertions(+)
 create mode 100644 PyExpLabSys/drivers/geopal_gpu45.py

diff --git a/PyExpLabSys/drivers/geopal_gpu45.py b/PyExpLabSys/drivers/geopal_gpu45.py
new file mode 100644
index 00000000..e96b5901
--- /dev/null
+++ b/PyExpLabSys/drivers/geopal_gpu45.py
@@ -0,0 +1,49 @@
+import serial
+import minimalmodbus
+
+
+class GeopalGP45(object):
+    error_codes = {
+        1: 'Alarm Low',
+        2: 'Alarm High',
+        3: 'Fault',
+        4: 'Ok',
+        5: 'No sensor'
+    }
+
+    def __init__(self, tty: str, instrument_address: int = 100):
+        self.comm = self._setup_comm(instrument_address, tty)
+
+    def _setup_comm(self, instrument_address: int, tty: str):
+        comm = minimalmodbus.Instrument(tty, instrument_address)
+        comm.serial.baudrate = 9600
+        comm.serial.parity = serial.PARITY_EVEN
+        comm.serial.timeout = 0.2
+        comm.serial.stopbits = 1
+        comm.serial.bytesize = 8
+        return comm
+
+    def _read(self, register):
+        # todo: Add some error checks...
+        value = self.comm.read_register(register, functioncode=3)
+        return value
+
+    def read_sensor(self, channel: int):
+        value_register = channel * 100
+        error_register = value_register + 1
+        value = self._read(value_register)
+        error_code = self._read(error_register)
+        return value, error_code
+
+
+if __name__ == '__main__':
+    geopal = GeopalGP45('/dev/ttyUSB0')
+
+    print(geopal.read_sensor(1))
+    print(geopal.read_sensor(2))
+    print(geopal.read_sensor(3))
+    print(geopal.read_sensor(4))
+    print(geopal.read_sensor(5))
+    print(geopal.read_sensor(6))
+    print(geopal.read_sensor(7))
+    print(geopal.read_sensor(8))