Help me now i must write program control washing machine use RTX ,can give me some hints?
"I must write program..."
So you had better start writing, then...
Actually, that would be a bad approach.
Before you start writing code, you should design your solution to your problem.
In order to design your solution, you are going to have to thoroughly study the specification of your Requirements
You need to know what wash programmes and other "user features" your machine must provide, and what external interfaces your software has to interact with; eg:
Motors & pumps; Water valves & level sensors; Water Heater; Temperature sensors; Vibration sensors; User interface; etc, etc,...
With motors, relays and whatever, make sure you design is EMI resistant/tolerant.
Erik
PS that, of course is hardware and thus not a Keil issue, but I can hardly count the number of projects that have missed on this account because of 'cost savings' such as 2 layer boards instead of proper 4 layer boards etc.