635   unsigned char csum = 0;  local
654       csum += buf[i];
658   *p++ = tohex ((csum >> 4) & 0xf);
659   *p++ = tohex (csum & 0xf);
753   unsigned char csum;  in read_frame()  local
757   csum = 0;  in read_frame()
784 	    if (csum == pktcsum)  in read_frame()
793 				  pktcsum, csum);  in read_frame()
800 	  csum += c;  in read_frame()
802 	  csum += c;  in read_frame()
821 	      csum += c;  in read_frame()