Expert
I contacted the expert about German machines (Progresssauger on youtube).
He gave some interesting information. The Bosch A500 was actually built by Zanker for Bosch. There was a model with spinner too, a twin tub.
The round symbol is for the drum and the square one for the detergent dispenser. If you select A for prewash and main wash, you put both detergent on the drum and in the dispenser. Wool gets only one wash, so you put the detergent on top of the drum. For starching and one rinse with softener it was also advised to put the starch or softener in an indentation on top of the drum, so it would be added to the water when the drum would start tumbling.
I contacted the expert about German machines (Progresssauger on youtube).
He gave some interesting information. The Bosch A500 was actually built by Zanker for Bosch. There was a model with spinner too, a twin tub.
The round symbol is for the drum and the square one for the detergent dispenser. If you select A for prewash and main wash, you put both detergent on the drum and in the dispenser. Wool gets only one wash, so you put the detergent on top of the drum. For starching and one rinse with softener it was also advised to put the starch or softener in an indentation on top of the drum, so it would be added to the water when the drum would start tumbling.