PSM Arithmetic, Example Of PSM Function - GF54.21-D-3055-01TSL

Model 447, 448 

with code ED5 (Parameterisable special module) 

with code XM7 (MOPF II) 

Vehicle interior temperature, constants 

Model 907, 910 

with code ED5 (Parameterisable special module) 

with code XJ4 (Modification year G4-I) 

Vehicle interior temperature, constants 

Courtesy of MERCEDES-BENZ USA

Vehicle interior temperature function blocks 

The vehicle interior temperature (interior CAN (CAN B): "AirTemp_Insd") can be output at one of the pulse-width-modulation-compatible outputs.

Formula: Duty cycle = (Vehicle interior temperature [°C] * 4)/232 [°C]

Value range of vehicle interior temperature	0 to 58°C
Value range of pulse-width-modulated signal	0 to 100%
Frequency	200 Hz

If no air conditioning system is installed ("KLA_VH = [0]"), then the output is constantly applied (i.e. pulse width modulation (PWM) = 100%).

The vehicle interior temperature is realized through the programmable logic control (PLC) group, arithmetic unit (AU) and the "MFA" blocks. The picture shows the simplified function block operation. The configuration is available in the tables.

Function description of implementation 

PLC G9 value table 1 (WT1 PLC G9Y  .

• Forward vehicle interior temperature if air conditioning system is installed, otherwise default value is output.

Comparator 6, calculation step 1 (Comp 6): 

• Check whether vehicle interior temperature is within the valid value range. If yes, output 1.

Comparator 7, calculation step 2 (Comp 7): 

• Check whether vehicle interior temperature is limited to valid value range.

Arithmetic unit memory (Memory 1): 

• Output valid signal, otherwise output last stored value.

PLC G12 flip-flop 2 (FF2): 

• Output 1 if a valid signal is received after wake-up.

PLC G8 value table 1 (WT 1 PLC G8): 

• If valid signal was received, result is output from memory; otherwise, the default value.

Calculation block 10, calculation step 4 (Calc 10): 

• Conversion of valid signal 0 to 232 to 232 to duty cycle 0 to 10.000

-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	Signal name	Signal ID
Input	F1	F2	F3	F4	F5	F6	F7	F8	F9	F1 0	F1 1	F1 2	F1 3	F1 4	F1 5	F1 6	Signal name	Identification number (ID) of signal	Default value (Signal name)	AU_Const_14	0xF045
WT1_1 (Value 1)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	HVAC_AVL	0x12E7	Value 1 (Signal name)	AirTemp_Insd	0x3075
WT1_2 (Value 2)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	Const_Bit_0	0x1000	Value 2 (Signal name)	Const_Bit_0	0x1000
WT1_3 (Value 3)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	Const_Bit_0	0x1000	Value 3 (Signal name)	Const_Bit_0	0x1000
WT1_4 (Value 4)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	Const_Bit_0	0x1000	Value 4 (Signal name)	Const_Bit_0	0x1000

Input	Signal name	Signal ID	Compare operation
Compare_6_a	AU_Const_14	0xF045	Input a (a) ≥ Input b (b)
Compare_6_b	SPS_G9_WT1	0xB073
Compare_6_c	Const_Bit_1	0x1001
Compare_6_d	Const_Bit_0	0x1000

Input	Signal name	Signal ID	Terminal 58D, comparator block
Compare_7_a	AU_Const_14	0xF045	Input a (a) ≥ Input b (b)
Compare_7_b	SPS_G9_WT1	0xB073
Compare_7_c	SPS_G9_WT1	0xB073
Compare_7_d	Const_Bit_0	0x1000

Input	Signal name	Signal ID	Arithmetic unit memory	-
Memory_1_Value	AU_Compare_7	0xF02E	-	Activation delay (in increments of 0 20 ms)
Memory_1_Enable	AU_Compare_6	0xF02D		-

Input	F1	F2	F3	F4	F5	F6	F7	F8	F9	F1 0	F1 1	F1 2	F1 3	F1 4	F1 5	F1 6	Signal name	Signal ID	Mode	Sequential point (1)
FF2_1 (Set/data)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	AU_Calc_4	0xF003	Threshold A	0
FF2_2  (Reset/clock)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	-	-	Threshold B	800

-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	PLC G8 value table 1 configuration	-	Signal name	Signal ID
Input	F 1	F 2	F 3	F 4	F 5	F 6	F 7	F 8	F 9	F 1 0	F 1 1	F 1 2	F 1 3	F 1 4	F 1 5	F 1 6	Signal name	Signal ID		Default value (Signal name)	AU_Const_14	0xF045
WT1_1 (Value 1)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	SPS_G12_FF2	0xB091		Value 1 (Signal name)	AirTemp_Insd	0x3075
WT1_2 (Value 2)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	Const_Bit_0	0x1000		Value 2 (Signal name)	Const_Bit_0	0x1000
WT1_3 (Value 3)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	Const_Bit_0	0x1000		Value 3 (Signal name)	Const_Bit_0	0x1000
WT1_4 (Value 4)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	Const_Bit_0	0x1000		Value 4 (Signal name)	Const_Bit_0	0x1000

Input	Signal name	Signal ID	Upper limit value	Lower limit value
Calc_10_a	SPS_G8_WT1	0xB066	1, 000	0
Calc_10_m1	AU_Const_12	0xF043
Calc_10_m2	AU_Const_14	0xF045
Calc_10_b	Const_Bit_0	0x1000

Constants	Arithmetic unit	Meaning
Constant 12	10, 000	Maximum duty cycle
Constant 13	2, 000	Frequency
Constant 14	250	Maximum valid value of interior CAN (CAN B) signal

1A high-side, PWM	F 1	F 2	F 3	F 4	F 5	F 6	F 7	F 8	F 9	F 10	F 11	F 12	F 13	F 14	F 15	F 16	Signal name	Signal ID	MFA 9	-
MFA9_Eingang1 MFA9_Input1 (Active)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	Const_Bit_1	0x1001	-	Type	Output (1)
MFA9_Eingang2 MFA9_Input (Const/pulse)	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	Const_Bit_0	0x1000		Reactivation attempts	1
MFA9_Eingang3 MFA9_Input3 (Cutoff reset)	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	Term15_Actv	0x1106		PWM type	Frequency (0)
MFA9_Eingang4 MFA9_Input4 (Cycle time)	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	Const_Bit_0	0x1000	-
MFA9_Eingang5 MFA9_Input5 (Pulse time)	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	Const_Bit_0	0x1000
MFA9_Eingang6 MFA9_Input6 (PWM active)	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	Const_Bit_1	0x1001
MFA9_Eingang7 MFA9_Input7 (PWM cycle)	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	AU_Const_13	0xF044
MFA9_Eingang8 MFA9_Input8 (PWM duty)	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	AU_Calc_10	0xF009