VXi VT1422A Manual Do Utilizador

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The <source_code> parameter can be one of three different SCPI types:

-- Quoted String: For short segments (single lines) of code, enclose the 

code string within single (apostrophes) or double quotes. Because of 
string length limitations within SCPI and some programming platforms, 
it is recommended that the quoted string length not exceed a single program 
line. Examples:

ALG:DEF 'ALG1','O108=I100;' or ALG:DEF 'ALG3','PIDA(I100,O124)'

Definite Length Block Program Data: For longer code segments (like complete 
custom algorithms), this parameter works well because it specifies the exact length 
of the data block that will be transferred. The syntax for this parameter type is:

#<non-zero digit><digit(s)><data byte(s)>

Where the value of <non-zero digit> is 1-9 and represents the number of <digit(s)>. 
The value of <digit(s)> taken as a decimal integer indicates the number of <data 
byte(s)> in the block. Example from "Quoted String" above:

ALG:DEF  'ALG1',#211O108=I100;Ø     (where "Ø" is a null byte)

For Block Program Data, the Algorithm Parser requires that the <source_code> data 
end with a null (0) byte. The null byte must be appended to the end of the block's 
<data byte(s)> and account for it in the byte count <digit(s)> from above. If the null 
byte is not included or <digit(s)> doesn't include it, the error "Algorithm Block must 
contain termination '\0'" will be generated.

Indefinite Length Block Program Data: This form terminates the data transfer 
when it receives an End Identifier with the last data byte. Use this form only when it 
is certain that the controller platform will include the End Identifier. If it is not 
included, the ALG:DEF command will "swallow" whatever data follows the 
algorithm code. The syntax for this parameter type is:

#0<data byte(s)><null byte with End Identifier>

 Example from "Quoted String" above:

ALG:DEF  'ALG1',#0O108=I100;Ø     (where "Ø" is a null byte)

For Block Program Data, the Algorithm Parser requires that the <source_code> data 
end with a null (0) byte. The null byte must be appended to the end of the block's 
<data byte(s)>. The null byte is sent with the End Identifier. If the null byte is not 
included, the error "Algorithm Block must contain termination '\0'" will be generated.