636   unsigned char csum = 0;  local
655       csum += buf[i];
659   *p++ = tohex ((csum >> 4) & 0xf);
660   *p++ = tohex (csum & 0xf);
754   unsigned char csum;  in read_frame()  local
758   csum = 0;  in read_frame()
785 	    if (csum == pktcsum)  in read_frame()
794 				  pktcsum, csum);  in read_frame()
801 	  csum += c;  in read_frame()
803 	  csum += c;  in read_frame()
822 	      csum += c;  in read_frame()