| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the competition of a shared memory between a transmission side processor and a reception side processor by allowing the transmission side processor to stop writing in a memory at a prescribed position, and allowing the transmission side processor to wait while the reception side processor reads the written data. SOLUTION: The value of a put pointer indicates the next position for writing by a transmission side processor in a shared memory, and the value of a get pointer indicates the next position for reading by a reception side processor from the shared memory. The writing processor can judge whether or not a writing validating area is present in the memory, and the reading processor can judge whether or not residual data to be read are present by comparing this put pointer with the get pointer. A microprocessor 173 stops writing in the memory in a prescribed time for reducing the number of times of the competition of the shared memory between the two processors. Then, a printer interface microprocessor independently performs access to the memory until it follows up.</p> |
