Device for and method of generating interrupt signals

An interrupt signal generating device comprising:

• interrupt detection units each adapted to output a detection signal in response a respective input signal representing an interrupt event;
• an interrupt handler unit adapted to receive the detection signals and having an output terminal for outputting corresponding interrupt signals to a CPU, and
• a state memory for storing information identifying the detection signals output from the interrupt detection units,
• wherein the interrupt handler unit is adapted to store in the state memory information identifying a detection signal received while the CPU executes a current interrupt process, and to output, after the current interrupt process ends, a corresponding interrupt signal from said output terminal based on the identifying information stored in the state memory.

A method of generating interrupt signals and applying the interrupt signals to a CPU, said method comprising the steps of:

• (a) monitoring a plurality of input terminals for the occurrence of detection signals representing interrupt events;
• (b) assigning each input terminal to any one of a plurality of output terminals;
• and
• (c) outputting an interrupt signal from a corresponding one of the output terminals, when step (a) detects a detection signal at an input terminal assigned with that output terminal.

A printer comprising:

• a CPU;
• interrupt detection units each adapted to output a detection signal in response to a respective input signal representing an interrupt event;
• and
• an interrupt handler unit, the interrupt handler having
• a plurality of input terminals for receiving the detection signals and a plurality of output terminals for outputting corresponding interrupt signals to the CPU, and
• a signal distributor coupling said input terminals to said output terminals and establishing a predetermined and changeable assignment between the input and output terminals, wherein each of said input terminals is assigned to one of said outputs terminals such that one of said interrupt signals is output from a corresponding output terminal in response to a detection signal applied to its assigned input terminal.

A printer comprising:

• a CPU;
• interrupt detection units each adapted to output a detection signal in response a respective input signal representing an interrupt event;
• an interrupt handler unit adapted to receive the detection signals and having an output terminal for outputting corresponding interrupt signals to the CPU, and
• a state memory for storing information identifying the detection signals output from the interrupt detection units,
• wherein the interrupt handler unit is adapted to store in the state memory information identifying a detection signal received while the CPU executes a current interrupt process, and to output, after the current interrupt process ends, a corresponding interrupt signal from said output terminal based on the identifying information stored in the state memory.