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Hi,

I am using a CR3000 connected to a S::CAN G series UV spectrometer where I'm trying to control, take measures and return data results in an event based system.

It connects via a propritory S::CAN "Connect" interface which supplies power(12v) and allows connection via USB(laptop) and RS485(logger).
Protocol is Modbus.

I am using a MD485 interface.

For testing I have public floats for all inputs of the modbus command to test returns and run the following.

If SCANRegistery = true Then
Timer (2,mSec,2)
ModbusMaster (RC,ComSDC7,38400,BusAddress,BusFunction,Variable,RegStartAddress,Length,3,100,Option)

SCANRegistery = false
Elapsed(2) = Timer (2,mSec,4)
EndIf

Although I am held by NDA about specfific registry entry names and numbers, I can descibe the problem I am having and how it relates to CRbasic.

I have a problem with data types, or specifically the limited data types of CRbasic; Float,long,Boolean and String.

The device input registers 16bit RO, holding registers RW use various data types

Char[x], string, x bytes
Bitmask, bitmask of 16 units, 2 bytes
Int16, signed 16 bit integer, 2 bytes
Uint16 unsigned 16 bit integer, 2 bytes
Float IEEE754 floating point, 4 bytes
enum, enum type, 2 bytes
timestamp(TAI64N), timestamp, 6 bytes

Because CRbasic has only 4 types, I cannot access, request or switch anything but the Floats contained in the registers.

I specfifically need enum to control switching 0,1 and 0,1,2
which control meausrement, modes such as on/off on/off/auto

I saw a note about firmware OS27(which is what my CR3000 is at) has issues with error codes not reporting, which I think I need, but I need help on creating enum in CRbasic or ways to fool the device that it is a an enum being sent/ retrieved.

thanks
Nigel

Public Result(10) As Long
Public single As Float
Public integer As Long
Public temp(5) As Long
Public str As String * 20

BeginProg
  Scan (10,Sec,0,0)

    'Float IEEE754 floating point, 4 bytes
    'READ
    ModbusMaster (Result(1),Com1,115200,1,3,single,1,1,1,100,2)
    'WRITE
    ModbusMaster (Result(2),Com1,115200,1,16,single,1,1,1,100,2)

    'Int16, signed 16 bit integer, 2 bytes
    'READ
    ModbusMaster (Result(3),Com1,115200,1,3,integer,1,1,1,100,1)
    'WRITE
    ModbusMaster (Result(4),Com1,115200,1,16,integer,1,1,1,100,1)

    'Bitmask, bitmask of 16 units, 2 bytes
    'Uint16 unsigned 16 bit integer, 2 bytes
    'enum, enum type, 2 bytes
    'All of these are unsigned 16 bit integers
    'READ
    ModbusMaster (Result(6),Com1,115200,1,3,integer,1,1,1,100,3)
    'WRITE
    ModbusMaster (Result(7),Com1,115200,1,16,integer,1,1,1,100,3)

    'Char[x], string, x bytes
    'READ
    'Read modbus registers containing ASCII characters
    'into array of LONG. Then move the bytes of the array
    'into a local STRING variable.
    ModbusMaster (Result(8),Com1,115200,1,3,temp,1,5,1,100,2)
    MoveBytes (str,0,temp,0,20)
   
    'Char[x], string, x bytes
    'WRITE
    'Move bytes of local STRING variable into array of LONG.
    'Write modbus registers with data in array of LONG.
    MoveBytes (temp,0,str,0,20)
    ModbusMaster (Result(9),Com1,115200,1,16,temp,1,5,1,100,2)

  NextScan
EndProg