During I/O process by reader/punch interface 1, the data set ready input signal of the I/O device (DR) was OFF. Possible causes are an I/O device not turn on, a broken cable, and a defective printed circuit board.
Check RS232 parameters 20, 101, 102, 103 and I/O setting. Try sending other direction. If parameters OK then port on control or PC could be faulty.