1. OptoControlSDKR40.exe Driver
2. ArcBuffr.Txt File Contents

ArcBuffr.Txt Driver File Contents (OptoControlSDKR40.exe)

ArcBuffr.Txt 
12/8/97

This ReadMe.Txt file explains the format of the Arcnet buffers for Mistic 
commands and responses. For a list of Mistc controller commands, refer 
to 'HostWords' and/or the file "Cool4th.Doc" which is included in the 
OptoControl SDK as well as the OptoDriver Toolkit.

Arcnet buffers are 'split' into two sections: [1] the first three bytes 
which specify the destination address and the length of data and [2] the data
itself which located at the end of the Arcnet buffer. The bytes in the middle
are disregarded. The table below describes how Arcnet buffers are organized.
---	-------------------------------------------------------------------------
Adr Description
---	-------------------------------------------------------------------------
00	Source or 'this' Arcnet node ID. Filled in by Arcnet chip.
01	Destination Arcnet node ID.
02	Offset of data in the buffer. Equal to 0x100 minus Length of data.
...
XX	First byte of command. XX = 0x100 minus Length of data.
...

FF	Last byte of command.
---	-------------------------------------------------------------------------


The following two tables are examples for the 'PTIME' command which 
requests the Mistic controller's time. This command is five upper-case
characters "PTIME" and the response is 8 bytes, something like "12:30:59".


Command buffer:
---	 ----  ------------------------------------------------------------------
Adr	 Data  Description
---	 ----  ------------------------------------------------------------------
00   N/A   Source or 'this' Arcnet node ID. Filled in by Arcnet chip.
01   xx    Destination Arcnet node ID. May be 1 to 0xFF.
02   F8    Offset of data in the buffer. F8 = 0x100 - (5 + 3).
...
...        03 thru F7 not used for a command of this length.
...
F8   DA    Opto 22 Arcnet vendor ID. First of 8 data bytes.
F9   01    Command type. 01==command with sequence ID.
FA   ss    Sequence ID. May be any 8-bit value 00 to FF.
FB   50    'P' - First byte of command.
FC   54    'T' 
FD   49    'I' 
FE   4D    'M' 
FF   45    'E' - Last byte.
---	 ----  ------------------------------------------------------------------

Command notes:
* Length of data = Length of command (5 for 'PTIME') plus 3 for these three 
overhead bytes: 0xDA vendor ID, Message type and sequence ID.
* The command type in this example is '1' which indicates that the message
is a command with a sequence ID. The sequence ID will be echoed in the
response from the Mistic controller. A command type of '0' is a command with
no sequence ID which eliminates one overhead byte in which case the Data 
offset would be F9 instead of F8.
* The maximum length of a command, using sequence id checking, is FA or 250
bytes.


Response buffer:
---	 ----  ------------------------------------------------------------------
Adr	 Data  Description
---	 ----  ------------------------------------------------------------------
00   xx    Source Arcnet node ID. Should be equal to 'xx' in command above.
01   yy    'This' Arcnet node ID.
02   F5    Offset of data in the buffer. F5 = 100 - 0B
...
...        03 thru F4 not used for a command of this length.
...
F5   DA    Opto 22 Arcnet vendor ID. First of x data bytes.
F6   00    Error code. 0 = no error.
F7   ss    Sequence ID. Should be equal to 'ss' in command above.
F8   31    '1' - First byte of response.
F9   32    '2' 
FA   3A    ':' 
FB   33    '3' 
FC   30    '0' 
FD   3A    ':' 
FE   35    '5' 
FF   39    '9' - Last byte of response
---	 ----  ------------------------------------------------------------------

Response notes:
* Length of response =  FD - DataOffset = FD - F5 = 8. "12:30:59" is 8 bytes 
long. Some responses, such as empty ACKs have a length of zero. An example is
the response to the power-up-clear command 'A'.
* If sequence ID checking is not used, one overhead byte is eliminated and
the Data offset would be F6 instead of F5.
* The maximum length of a response, using sequence id checking, is FA or 250
bytes. 


(End)