Method and circuit for testing an analog-to-digital converter module on a data processing system having an intermodule bus

In a data processing system having a central processing unit, a plurality of modules, and an intermodule bus for coupling the plurality of modules to the central processing unit, a module of the plurality of modules having an input/output port, and the module having a plurality of sub-modules, a method of testing a sub-module of the plurality of sub-modules, comprising the steps of:

• coupling each of the sub-modules and the input/output port to a test bus, the test bus being different than the intermodule bus;
• providing test setup information to the sub-module via the intermodule bus;
• testing the sub-module;
• and
• providing test results of the sub-module to a tester that is external to the data processing system via the test bus to the input/output port.

In a data processing system having a central processing unit, a plurality of modules, and an intermodule bus for coupling the plurality of modules to the central processing unit, a module of the plurality of modules being an analog-to-digital converter (ADC), the ADC having a plurality of sub-modules and an input/output port, a method of testing the ADC comprising the steps of:

• coupling the plurality of sub-modules to the input/output port using a test bus, the test bus being different than the intermodule bus;
• applying ADC test mode signals to the ADC via the intermodule bus to place the ADC into a test mode;
• applying an analog input signal to the ADC via the input/output port;
• applying a start signal to cause the ADC to begin a conversion process;
• reading a digital value from the ADC after the conversion process to determine that the digital value compares favorably to a predicted result;
• and
• providing the predicted result to the input/output port via the test bus.