B&B Electronics RS-485 manual AddrRA#, Ch#MSBch#LSBch#-1MSB...ch0MSBch0LSB, Read A/D Response

The Read A/D channels command returns two bytes for each channel read. The two bytes represent the most significant byte (MSB) and least significant byte (LSB) of the reading. The MSB is received first, followed by the LSB. This command requires a data byte. The data byte is used to specify the number of the highest channel to be read. All channels less than this channel will be read as well. For example, if the data byte has a value of 6, then channels 0 to 6 will be read. The highest channel is read first. Command Syntax

!{addr}RA{#}

Where “{#}” is a byte that specifies the number of the highest channel to be read. See Table 3.3

Response Syntax

{ch(#)MSB}{ch(#)LSB}{ch(#-1)MSB}...{ch0MSB}{ch0LSB}

The most significant byte of the channel specified is received first. The least significant byte and the lower channels will follow in descending order. “{chxMSB}” and “{chxLSB}” represent the most and least significant bytes of the A/D conversion result.

Table 3.3 - Read A/D Response

# of Channels Specified			Response
			Channels Returned	Bytes
decimal	Hex	ASCII	(order of response)	Returned
0	0	NUL	Channel 0	2
1	1	SOH	Channels 1,0	4
2	2	STX	Channels 2,1,0	6
3	3	ETX	Channels 3,2,..,0	8
4	4	EOT	Channels 4,3,..,0	10
5	5	ENQ	Channels 5,4,..,0	12
6	6	ACK	Channels 6,5,..,0	14
7	7	BEL	Channels 7,6,..,0	16
8	8	BS	Channels 8,7,..,0	18
9	9	HT	Channels 9,8,..,0	20
10	A	LF	Channels 10,9,..,0	22

NOTE: There are three test channels that can be read: Ref+, Ref-, and Ref+/2. Specify 13 (0Dh) to read Ref+, 12 (0Ch) to read Ref-, and 11 (0Bh) to read Ref+/2.

14 485SDA103798 Manual

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