							10/24/89
							02/28/90 (Rev)

		193 Devices Front End Support


		Aggregate Ring-Wide Devices
		--------- ---- ---- -------

Basic SSDN pattern:  6EFF/0601/000s/dddd

			0601  crate and slot  (crate 01 for ring-wide)
			s     sub-code
			dddd  default error value (for ring-wide devices)


		SSDN	Size	
M:NAME	PROP	code	words	Description

VGSCMD	SETTNG	1	24	Snapshot arm and trigger command
VGSDLY	SETTNG	2	24	Snapshot delay (ms)
VGSNAP	READNG	3	24x10	Snapshot data
VGHSTA	READNG	4	24	Module hardware status
VGSSTA	READNG	5	24	Module software status
VGTRAN	READNG	6	24x9	1 point of transient recorder data (mode 3)
VGTCMD	SETTNG	7	24	Transient recorder arm and trigger cmnd
VGTDLY	SETTNG	8	24	Transient recorder delay
VGTPER	SETTNG	9	24	Transient recorder sample period
VGV2G	READNG	A	24x8	Voltages to ground
VGV2GP	READNG	B	24x32	Peak Voltages to ground
  "	BCNTRL	B	24	Reset Peak voltages to ground	
VGSEV	SETTNG	C	8	Snapshot clock events
VGTEV	SETTNG	D	8	Transient recorder arming clock events
VGRST	SETTNG	E	8	Time stamp reset clock events
VGFTOD	READNG	F	9	Time of day stamp for last fast trip

General Notes
------- -----

    The notation 24xN means that there are N blocks, each 24 words long.
Thus you would use a Fortran array dimensioned (24,N).

    For the setting and basic control properties (except for the clock
event devices) you send a SINGLE WORD, which the front end will replicate
in all houses.  The reading-the-setting operations will return the same
data from all 24 houses (which presumably should be identical).

    You cannot use length and offset slicing on the big buffers.  You can
return a partial buffer, however, as long as you keep the length at an
exact multiple of 24 words.

    On any reading, if there is an error trying to read the 193 card
the front end will put the default error value in place of that
individual 193 card's slot in the 24 word array.  In this way, a
single point of failure will not prevent the application page from 
working.  The default error value is obtained from the SSDN.  For
the voltage channels, it probably ought to be 8000 (hex) = -10.24 V,
which ought to stand out on a plot.


Snapshot Data Device
-------- ---- ------

    Remember that this device returns 10 blocks of 24 words.

    Block 1:	   F(0)A(0) time stamp
    Blocks 2 - 9:  F(0)A(n) data from channel n (all 8 channels)
    Block 10:	   F(0)A(9) snapshot serial number


Transient Recorder Data Device
--------- -------- ---- ------

    This device obtains a single point for all 8 channels.  Data is
read from the 193 card using mode 3: a time stamp followed by channels
1 through 8.

    You can obtain only a single point (for all 8 channels) with one 
reading of this device.  You specify which point you want by putting
twice the point number (0 - 4094) (i.e. 0*2 - 2047*2) in the "offset"
parameter of the DPREQ call.

    This device is probably useful only as a one-shot read.

    Block 1:	   Time stamp
    Blocks 2 - 9:  Channels 1 - 8

    Note that in the database the reading property is declared with
an unusual length:

	PRO READNG (2, 4528, 60)

The length is 432 bytes (the amount you always read) plus 4094 (the maximum
"offset" code).  We do this to fool the data pool routines, which audit the
length and "offset" in your DPREQ call against the maximum length in the
database.


Voltages to Ground
-------- -- ------

    Blocks 1 - 8:  Channels 1 - 8


Peak Voltages to Ground
---- -------- -- ------

    Sending a single basic control word on this device (any value
of basic control word will do) will reset the peaks.

    Block 1:	   Time Stamp for channel 1 peak minimum value
    Block 2:	   Channel 1 peak minimum value
    Block 3:	   Time Stamp for channel 1 peak maximum value
    Block 4:	   Channel 1 peak maximum value
    Blocks 5 - 32: Repeat for channels 2 through 8 (4 blocks / channel)


Clock Event Devices
----- ----- -------

    You can specify as many events as you want.  You pack them into a
buffer (a byte at a time) and place a count in the first byte.  The
buffers can be any (even number of bytes) length.  We will make
them 8 words in the data base, for a maximum of 15 events.  The count
must start with 1.  The buffer thus looks like this:

			+-------+-------+
			| evt 1 | count |
			+-------+-------+
			| evt 3 | evt 2 |
			+-------+-------+
			~       ~       ~
			~       ~       ~
			+-------+-------+
			| evt 15| evt 14|
			+-------+-------+

     Note that it is not possible to read the counts back from the
cards.


Time of Day Stamp For Fast Trips
---- -- --- ----- --- ---- -----

     When a fast trip occurs, event 23 is issued on TCLK.  The front
end records the date and time in a 9 word (18 byte) ASCII buffer, so
the application can put this time stamp on the resulting voltage to
ground plot.

     The device's name is M:VGFTOD.  You should always read exactly
18 bytes.  The ASCII time stamp looks like:

		DD-MMM-YY HH:MM:SS
		^                ^
	     Byte 0           Byte 17



			Single Channel Devices
			------ ------- -------

Basic SSDN pattern:  6DFF/nncc/000a/0000

			nncc  crate and slot
			a     subaddress (1-8)
    
These are standard 1 word reading properties.
There is a reading PDB which scales 1 V (A/D) = 200 V (measured)

M:NAME	Subaddr

LA1P	1
LA1M	2
UA1P	3
UA1M	4
QA1P	5
QA1M	6
