PowerTec DFS-1 manual Unit ID, Local / Remote Control, Number Baud Rate, Not Used

3.0DFS-1 PARAMETERS

DFS-1 parameters are stored as DOUBLE WORD values (32 bits), regardless of the actual size of the data. This method is used to simplify the entire system at a cost of a little extra data storage.

A double word consists of four BYTES (8 bits). Each byte is a hexadecimal (base 16) value which ranges from 00h (0 decimal) to FFh (255 decimal). The largest number used in the DFS-1 parameters is 99,999 decimal, which, in hexadecimal notation is 0001 869Fh.

In many cases, information other than numbers is passed and stored in the parameters. The left byte is the most significant and the last byte is the least significant. The arrangement of the bytes for this purpose is: VL4 VL3 VL2 VL1 where VL4 is the Most Significant Bit (MSB) and VL1 is the Least Significant Bit (LSB). Each parameter breaks down the bytes accordingly.

All four bytes are required in communications. A number which must be either 0 or 1 must be passed as either 0000 0000h or 0000 0001h.

1.UNIT ID

USE PARAMETER #1 TO IDENTIFY THE AD- DRESS OF THE UNIT ON A NETWORK. RANGE OF VALUES: 0000 0001h to 0000 00FFh

1 to 255 (decimal)
Default Value: 0000 0001h	1 (decimal)

The Unit ID number is installed in parameter #1. This serves as an address on the external communica- tions link. Two DFS-1 units cannot have the same address while installed on the same communications link.

There are 254 possible addresses if the default value of 1 is not used as an address. Since the default value is 1, there could be a problem if a new unit is installed without changing the #1 parameter.

2.BAUD RATE

USE PARAMETER #2 TO SET THE COMMUNI- CATIONS SPEED OF THE NETWORK. RANGE OF VALUES: 0000 0000h to 0000 0007h

0 to 7 (decimal)
Default Value: 0000 0002h	2 (decimal)

This establishes the rate at which data is ex- changed in the communications link. Every DFS-1 in the communications link must have the same baud

rate set up in parameter #2. The parameter selects from among eight industry standard baud rates:

NUMBER	BAUD RATE
0000 0000h	38.4 Kilobaud		(38,400 baud)
. . . . 01	19.2 Kilobaud		(19,200 baud)
. . . . 02	9,600	baud
. . . . 03	4,800	baud
. . . . 04	2,400	baud
. . . . 05	1,200	baud
. . . . 06	600	baud
. . . . 07	300	baud

3.LOCAL / REMOTE CONTROL

USE PARAMETER #3 TO SET UP WHICH FUNCTIONS ARE CONTROLLED REMOTELY. RANGE OF VALUES: 0000 0000h to 0000 007Fh

0 to 127 (decimal)
Default Value: 0000 0000h	0 (decimal)

Parameter #3 is first broken down into bytes, and then VL1 is further broken down into bits.

When broken down into bits, 00h = 0000 0000b, and 7Fh = 0111 1111b.

VL4 is always 00h. VL3 is always 00h. VL2 is always 00h.

VL1 is broken down into eight bits, which are numbered from right to left: 7654 3210h.

Functions are assigned as follows: Bit Position Function

7 NOT USED

6Master/Slave (not presently functional)

5Frequency Mode

4Reverse

3Down

2Up

1Preset

0Run

A zero in a bit position means that function may be controlled from an input terminal assigned to it. A one in a bit position means that the function may only be controlled via a communications link, such as the operator’s station connection or the external RS- 485 communications link.

For instance, if VL1 is given a value of 01 (0000

Revised 7/95	DFS-1 Manual	Page 19
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