JSF runs on HTTP, and HTTP's design, regardless of the framework or programming language used, is limited to request/response. When using input controls such as radio buttons, the request has to be part of a submitted form. Technically, therefore, a button cannot "call" a bean method. In fact, even "Submit" buttons don't actually "call" anything. What they do is submit the form and JSF parses the incoming data as part of its lifecycle processing, firing the control's action method (and/or notifying action listeners) as part of the lifecycle process.
Briefly, then, in order to emulate an interactive GUI desktop-style radio button action, you can't use basic JSF because it's based on basic HTML/HTTP.
However, you can use AJAX to get the desired behavior.
What you need to do is attach an AJAX request to the radiobutton. That AJAX request would then fire a backing bean method which would use the current value of the property named "codigo" to setup the updated display values. On return from the AJAX call, the changed parts of the page are re-rendered using the updated values from the backing bean.
How you handle AJAX depends on you. In JSF2, there's a new ajax tag, but a number of the third-party extension tagsets also provide AJAX services, and several of them work under JSF1 as well as JSF2.