i2c interface working, tested on the hardware

I2C_serial_pi.py

@@ -42,7 +42,7 @@ class I2C:
  #           sleep(0.2)
         except IOError, err:
             ret_ack = 0
-            ret_value = 0
+            ret_value = 'ffff'
             if DEBUG:
                 print("Reading error")
         return ret_ack, ret_value
@@ -50,17 +50,20 @@ class I2C:
     
     def read_last_reg(self, bytes_to_read):
         bus = smbus.SMBus(self.bus_nr)
-        ret_value=[]
-        for cnt in bytes_to_read:
+        rd_value = []
+        ret_value = ''
+        for cnt in range(bytes_to_read):
             try:
-                ret_value.append(bus.read_byte(self.I2C_Address))
+                rd_value.append(bus.read_byte(self.I2C_Address))
                 ret_ack = 1
  #               sleep(0.2)
             except IOError, err:
                 ret_ack = 0
-                ret_value = 0
+                rd_value.append(0)
                 if DEBUG:
                     print("Reading error")
+        for cnt in range(bytes_to_read):
+            ret_value += (hex(rd_value[cnt])[2:])
         return ret_ack,ret_value
   
     def write_bytes(self, register, data):

rd_unb2c.py

@@ -30,7 +30,6 @@ sys.path.insert(0, '.')
 I2CBUSNR = 3
 DEBUG = False
 
-
 class Unb2cClass:
     #
     # Class that contains all parts on a UniBoard2
@@ -44,11 +43,11 @@ class Unb2cClass:
         for pol in list(CTR_POLS.keys()):
             self.pols.append(PolClass(pol, location = "central"))
         self.dev_i2c_eeprom = I2C(EEPROM)
-        self.dev_i2c_eeprom.bus = I2CBUSNR
+        self.dev_i2c_eeprom.bus_nr = I2CBUSNR
         self.main_switch = I2C(MAIN_I2C_SWITCH)
-        self.main_switch.bus = I2CBUSNR
+        self.main_switch.bus_nr = I2CBUSNR
         self.front = I2C(LED_DRIVER)
-        self.front.bus = I2CBUSNR
+        self.front.bus_nr = I2CBUSNR
 
     def write_eeprom(self, data=0x01):
         #
@@ -125,6 +124,7 @@ class Unb2cClass:
             self.front_led(LED_COLORS[color])
         for node in self.nodes:
             node.print_status()
+        print("Status central UniBoard2 components")
         for pol in self.pols:
             pol.print_status()
         self.wr_rd_eeprom()
@@ -182,14 +182,14 @@ class NodeClass:
         # Before a node can ba accessed the i2c switches have to be set, this function can be used.
         #
         main_switch = I2C(MAIN_I2C_SWITCH)
-        main_switch.bus = I2CBUSNR
+        main_switch.bus_nr = I2CBUSNR
         ret_ack = main_switch.write_bytes(0x0, 0x01 << self.node_number)  # select Node
         if ret_ack < 1:
             if DEBUG:
                 print("Main I2C switch not found")
         else:
             node_switch = I2C(NODE_I2C_SWITCH)
-            node_switch.bus = I2CBUSNR
+            node_switch.bus_nr = I2CBUSNR
             ret_ack = node_switch.write_bytes(0x0, 0x20)  # select DDR4
             if ret_ack < 1:
                 if DEBUG:
@@ -210,14 +210,14 @@ class QsfpClass:
         self.status = False
         self.select_qsfp()
         self.qsfp_cage = I2C(QSFP_I2C_ADDR)
-        self.qsfp_cage.bus = I2CBUSNR
+        self.qsfp_cage.bus_nr = I2CBUSNR
 
     def select_qsfp(self):
         #
         # Function to set the I2C switch to access a QSFP cage
         #
         node_switch = I2C(NODE_I2C_SWITCH)
-        node_switch.bus = I2CBUSNR
+        node_switch.bus_nr = I2CBUSNR
         ret_ack = node_switch.write_bytes(0x0, QSFP_PORT[self.port])
         if ret_ack < 1:
             if DEBUG:
@@ -232,11 +232,14 @@ class QsfpClass:
         #
         self.select_qsfp()
         ret_ack, raw_ret = self.qsfp_cage.read_bytes(QSFP_TEMP, 2)
-        if (ret_ack < 1) | (raw_ret[:2] == 'ff'):
+        if ret_ack < 1:
             if DEBUG:
                 stri = "No QSFP found in port {0}".format(self.port)
                 print(stri)
             self.status = False
+        else:
+            if (raw_ret[0:2] == 'ff') | (len(raw_ret) < 4):
+                 self.status = False
             else:
                 ret_value = []
                 ret_value.append(int(raw_ret[:2], 16))
@@ -250,11 +253,14 @@ class QsfpClass:
         #
         self.select_qsfp()
         ret_ack, raw_ret = self.qsfp_cage.read_bytes(QSFP_VOLT, 2)
-        if (ret_ack < 1) | (raw_ret[:2] == 'ff'):
+        if ret_ack < 1:
             if DEBUG:
                 stri = "No QSFP found in port {0}".format(self.port)
                 print(stri)
             self.status = False
+        else:
+            if (raw_ret[0:2] == 'ff') | (len(raw_ret) < 4):
+                self.status = False
             else:
                 ret_value = []
                 ret_value.append(int(raw_ret[:2], 16))
@@ -293,14 +299,14 @@ class DdrClass:
             self.ddr_dev = I2C(MB_I_TEMP_I2C_ADDR)
         else:
             self.ddr_dev = I2C(MB_II_TEMP_I2C_ADDR)
-        self.ddr_dev.bus = I2CBUSNR
+        self.ddr_dev.bus_nr = I2CBUSNR
 
     def set_i2c_switch(self):
         #
         # Function to set the I2C switch to access the DDR4 modules
         #
         node_switch = I2C(NODE_I2C_SWITCH)
-        node_switch.bus = I2CBUSNR
+        node_switch.bus_nr = I2CBUSNR
         ret_ack = node_switch.write_bytes(0x0, DDR4)
         if ret_ack < 1:
             if DEBUG:
@@ -355,17 +361,18 @@ class PolClass:
         self.vout = 0
         self.iout = 0
         self.temp = 0
-        if self.location == "node":
         self.set_i2c_switch()
+        if self.location == "node":
             self.pol_dev = I2C(LOC_POLS[self.name])
         else:
             self.pol_dev = I2C(CTR_POLS[self.name])
-        self.pol_dev.bus = I2CBUSNR
-        sleep(0.1)
-        ret_ack, ret_value = self.pol_dev.read_bytes(0)
+        self.pol_dev.bus_nr = I2CBUSNR
+        ret_ack, ret_value = self.pol_dev.read_bytes(1)
         if ret_ack < 1:
-            if DEBUG:
+            if self.location == "node": # DEBUG:
                 stri = " Device {0} at address 0x{1:X} not found".format(self.name, LOC_POLS[self.name])
+            else:    
+                stri = " Device {0} at address 0x{1:X} not found".format(self.name, CTR_POLS[self.name])
             print(stri)
             self.status = False
         else:
@@ -375,15 +382,27 @@ class PolClass:
         #
         # Function to set the I2C switch to access the Point of Load DC/DC converter
         #
+        if self.location == 'node':
             node_switch = I2C(NODE_I2C_SWITCH)
-        node_switch.bus = I2CBUSNR
+            node_switch.bus_nr = I2CBUSNR
             ret_ack = node_switch.write_bytes(0x0, LOC_POWER)
             if ret_ack < 1:
                 if DEBUG:
                     print("Node I2C switch not found")
+                self.status = False
+            else:
                 self.status = True
         else:
+            main_switch = I2C(MAIN_I2C_SWITCH)
+            main_switch.bus_nr = I2CBUSNR
+            ret_ack = main_switch.write_bytes(0x10, 0x10)
+            if ret_ack < 1:
+                if DEBUG:
+                    print("Main I2C switch not found")
                 self.status = False
+            else:
+                self.status = True
+                return False
 
     def read_vout(self):
         #
@@ -392,9 +411,7 @@ class PolClass:
         if self.status:
             if type == "node":
                 self.set_i2c_switch()
-            sleep(0.1)
             ret_ack, vout_mod = self.pol_dev.read_bytes(LP_VOUT_MODE, 1)
-            sleep(0.1)
             ret_ack, raw_value = self.pol_dev.read_bytes(LP_VOUT, 2) 
             vout_mod = int(vout_mod, 16)
             ret_value = []
@@ -409,9 +426,7 @@ class PolClass:
         # Function to read the output current of the Point of Load DC/DC converter
         #
         if self.status:
-            if type == "node":
             self.set_i2c_switch()
-            sleep(0.1)
             ret_ack, raw_value = self.pol_dev.read_bytes(LP_IOUT, 2)
             ret_value = []
             ret_value.append(int(raw_value[:2], 16))
@@ -425,9 +440,7 @@ class PolClass:
         # Function to read the temperature of the Point of Load DC/DC converter
         #
         if self.status:
-            if type == "node":
             self.set_i2c_switch()
-            sleep(0.1)
             ret_ack, raw_value = self.pol_dev.read_bytes(LP_temp, 2) 
             ret_value = []
             ret_value.append(int(raw_value[:2], 16))
@@ -461,6 +474,7 @@ def main():
     # Function to test the class, read all info and dump on the screen
     #
     unb = Unb2cClass()
+    if unb.wr_rd_eeprom(value=0x34):
         unb.read_all()
         unb.print_status()