The AM-CRI is a card reader that will support one or two 26-bit, 30-bit, or 31-bit Wiegand input devices. If the readers used have a hold or buffer connection, two readers may be used to the AM-CRI. If the readers do not have a hold or buffer connection, one reader may be used with the AM-CRI. Usually mounted near the readers, the AM-CRI interface connects to the control unit through a PBUS cable. Each reader connects to the AM-CRI through a six-wire (one LED in reader) or seven-wire (two LEDs in reader) cable.