... soll doch nix wegschmeißen. [-X
Ich habe gerade den USER'S GUIDE für CP/NET aus dem Jahr 1980 (Digital Research) in der Hand.

Ich schreibe mal einige Stellen ab:
Code:
.-----.-----.-----.-----.-----.--------- - - -.
| FMT | DID | SID | FNC | SIZ | MSG           |
'-----'-----'-----'-----'-----'--------- - - -'
   |     |     |     |     |     |
   |     |     |     |     |     Actual Message, Size + 1 Bytes
   |     |     |     |     Size, Data field lenght -1
   |     |     |     CP/M, MP/M Function code
   |     |     Message souce processor ID
   |     Message destination processor ID
   Message format code


	Message Field Length Table
       .-----.-----.-----.-----.-----.-----.
FMT    | FMT | DID | SID | FNC | SIZ | MSG |
Code   '-----'-----'-----'-----'-----'-----'
 00       1     1     1     1     1     1-256	Preferred format	
 01       1     1     1     1     1     1-256	Returned result	
 02       1     1     1     1     2     1-65536
 03       1     1     1     1     2     1-65536 Returned result
 04       1     2     2     1     1     1-256
 05       1     2     2     1     1     1-256   Returned result
 06       1     2     2     1     2     1-65536
 07       1     2     2     1     2     1-65536 Returned result
Code:
CP/NET Logical Message Specification
ss = Server ID
rr = Requestor ID
xx = Don't care byte
nn = Value specified

 FMT  DID  SID  FNC  SIZ  MSG / Function Name         
.----.----.----.----.----.------------------------.
|    |    |    |    |    | System Reset           |
| 00 | ss | rr | 00 | 00 | 00-00 = xx             |
| 01 | rr | ss | 00 | 00 | 00-00 = 00             |
|----+----+----+----+----+------------------------|
|    |    |    |    |    | Console Input          |
| 00 | ss | rr | 01 | 00 | 00-00 = xx             |
| 01 | rr | ss | 01 | 00 | 00-00 = 00             |
|----+----+----+----+----+------------------------|
|    |    |    |    |    | Console Output         |
| 00 | ss | rr | 02 | 00 | 00-00 = xx             |
| 01 | rr | ss | 02 | 00 | 00-00 = 00             |
|----+----+----+----+----+------------------------|
|    |    |    |    |    | RAW Console Input      |
| 00 | ss | rr | 03 | 00 | 00-00 = xx             |
| 01 | rr | ss | 03 | 00 | 00-00 = 00             |
|----+----+----+----+----+------------------------|
|    |    |    |    |    | RAW Console Output     |
| 00 | ss | rr | 04 | 00 | 00-00 = xx             |
| 01 | rr | ss | 04 | 00 | 00-00 = 00             |
|----+----+----+----+----+------------------------|
|    |    |    |    |    |                        |
.    .    .    .    .    .                        .
|    |    |    |    |    |                        |
|----+----+----+----+----+------------------------|
|    |    |    |    |    | Return Version Number  |
| 00 | ss | rr | 0C | 00 | 00-00 = xx             |
| 01 | rr | ss | 0C | 00 | 00-00 = 00             |
|----+----+----+----+----+------------------------|
.    .    .    .    .    .                        .
|    |    |    |    |    |                        |
'----'----'----'----'----'------------------------'
Code:
Recommend Server-Requester Handshake for RS-232C
.-----.-----.-----.-----.-----.-----.-----.-----.-----.-----.-   -.-----.-----.-----.
| ENQ | SOH | FMT | DID | SID | FNC | SIZ | HCS | STX | MSG | ::: | ETX | CKS | EOT |         
'-----'-----'-----'-----'-----'-----'-----'-----'-----'-----'-   -'-----'-----'-----'
Messages format codes 00 & 01 are recommended

ENQ = Enquire, one byte, 05H
SOH = Start of Header, one byte, 01H
FMT,DID,SID,FNC,SIZ = as defined, onebyte per field
HCS = Header Checksum, one byte
STX = Start of Data, one byte, 02H
MSG = SIZ + 1 bytes long
ETX = End of Data, one byte, 03H
CKS = Checksum, one byte
EOT = End of Transmission, one byte, 04H

Source		Destination 	Comment
5 - ENQ	------->
        <------- ACK - 6

1 - SOH -------> 
    FMT ------->
    DID ------->
    SID ------->
    FNC ------->
    SIZ ------->
    HCS ------->	Modulo 256 sum from SOH to HCS = 0
        <------- ACK -6

2 - STX ------->
    DB0 ------->	First data Byte
        ....
    DBn ------->
3 - ETX ------->
    CKS ------->	Modulo 256 sum from STX to CKS = 0    
4 - EOT ------->
        <------- ACK -6