Blit down-load and communications protocols g byte order \f468ld\fP protocol for stand-alone down-loading \f468ld\fP protocol for down-loading \f4mpxterm\fP binaries \f4mpx\fP communications protocol Blit-\f4mpx\fP layer protocol channel number control packet error-corrected communication channel hangup signal multiplexed protocol terminal process timeout period -z option s 68ld -e 68ld -x mpx communication 68ld protocol 68ld options 68ld issues mpx channel mpxterm mpxterm menu Blit error-corrected packet protocol asymmetric protocol communications protocols