http://software.x10.com/pub/.../kr21a-is.pdf
KR21A DigiPad™ Remote installation and operating ... The KR21A works with the RR501 (part of the RC5000) and ... Press and hold the # 1 button. The red LED blinks once. 3 ... Release the # 1 ... Press and release the # 1 button the appropriate number of ...