diff --git a/frappy_psi/ls370res.py b/frappy_psi/ls370res.py
index 906846a..04cdea0 100644
--- a/frappy_psi/ls370res.py
+++ b/frappy_psi/ls370res.py
@@ -267,8 +267,7 @@ class ResChannel(Channel):
         if self.autorange:
             if rng < self.minrange:
                 rng = self.minrange
-        self.communicate('RDGRNG %d,%d,%d,%d,%d,%d;*OPC?' % (
-            self.channel, iscur, exc, rng, 0, excoff))
+        self.communicate(f'RDGRNG {self.channel},{iscur},{exc},{rng},0,{excoff};*OPC?')
         self.read_range()
 
     def fix_autorange(self):
@@ -290,12 +289,11 @@ class ResChannel(Channel):
 
     @CommonWriteHandler(inset_params)
     def write_inset(self, change):
-        _, _, _, curve, tempco = literal_eval(
+        _, _, _, change['curve'], change['tempco'] = literal_eval(
             self.communicate(f'INSET?{self.channel}'))
         self.enabled, self.dwell, self.pause, _, _ = literal_eval(
-            self.communicate('INSET %d,%d,%d,%d,%d,%d;INSET?%d' % (
-                self.channel, change['enabled'], change['dwell'], change['pause'], curve, tempco,
-                self.channel)))
+            self.communicate('INSET {channel},{enabled:d},{dwell:d},'
+                             '{pause:d},{curve},{tempco};INSET?{channel}'.format_map(change)))
         if 'enabled' in change and change['enabled']:
             # switch to enabled channel
             self.switcher.write_target(self.channel)
diff --git a/frappy_psi/ppms.py b/frappy_psi/ppms.py
index 697ae30..abb64b0 100644
--- a/frappy_psi/ppms.py
+++ b/frappy_psi/ppms.py
@@ -215,7 +215,7 @@ class DriverChannel(Channel):
         :param values: a dict like object containing the parameters to be written
         """
         self.read_params()  # make sure parameters are up to date
-        self.comm_write(f"DRVOUT {values['no']},{values['current']:g},{values['powerlimit']:g}")
+        self.comm_write('DRVOUT {no:d},{current:g},{powerlimit:g}'.format_map(values))
         self.read_params()  # read back
 
 
@@ -260,9 +260,8 @@ class BridgeChannel(Channel):
             values['excitation'] = 0
             values['powerlimit'] = 0
             values['voltagelimit'] = 0
-        self.comm_write(f"BRIDGE {values['no']},{values['enabled']:g},' \
-            f'{values['powerlimit']:g},{int(values['dcflag'])},{int(values['readingmode'])},' \
-            f'{values['voltagelimit']:g}")
+        self.comm_write('BRIDGE {no:d},{enabled:d},{powerlimit:g},{dcflag:d},'
+                        '{readingmode:d},{voltagelimit:g}'.format_map(values))
         self.read_params()  # read back