Spinal cord injury and other injuries and diseases of the nervous system often result in the inability to sense the need to empty the rectum or to control the timing of bowel movements. The blood processing filter, includes a first filter element for removing aggregates from blood, a second filter element for removing leukocytes provided in the downstream of the first filter element, and a third filter element having gas permeability of 3 to 40 cccm2sec per thickness of 1 cm provided between the second filter element and the outlet port. The interface logic circuit unit generates a signal for selecting the top or the bottom memory bank unit according to read or write command received from the external.