
Available protocols
-------------------

    <X>......Xmodem checksum
    <C>......Xmodem CRC
    <Y>......Ymodem (also known as Xmodem-1K)
    <YB>.....Ymodem Batch (also known as "true" Ymodem)
    <Z>......Zmodem
    <B>......BiModem
    <H>......HS/Link

