aci eRCM Express, Manual

Page: 71 / 97

mCore Firmware Ver 01.10 Ver 2019-Oct-29 Page 71 of 97
Modbus.Write()
TWO OPTIONS - DO ONE OR THE OTHER.
// Wait for eRCM Express to finish calculation (make a subroutine!)
// This fully guarantees that the data being read back is appropriate for
// the operating data sent to the eRCM Express.
Modbus.NumberOfDataValues = eRCM_IsKernelBusyLen
Modbus.Address = eRCM_IsKernelBusyStart
eRCMExpressCount = 0
DO
Sleep 20 ms
Modbus.ReadData() // Read data in the "IsKernelBusy" register.
If Modbus.Data(1) = 0 Then Exit DO // If 0, calculations now complete.
eRCMExpressCount = eRCMExpres 1
LOOP UNTIL eRCMExpressCount > 10 // Prevent Infinite Loop
IF eRCMExpressCount > 10 THEN
MSG “CRITICAL ISSUE: eRCM Express Unit does not appear to be returning
data.”
// NOTE: If gateway device used, you may need to wait longer for updates.
EXIT
END IF
// This method avoids needing to poll the IsKernelBusy register until it goes
// back to zero (0). Most calculations will complete in 150 ms. Thus, simply
// wait a long enough period to guarantee calculations are complete.
// However, for some models, you may need to wait 250-350 ms for completion.
Sleep 150 ms
Modbus.NumberOfDataValues = eRCM_
LStoSetforSULen
Modbus.Address = eRCM_ LStoSetforSU
Modbus.ReadData()
IF Modbus.Data(1) <> -1 THEN
CurrentLoadStep = Modbus.Data(1)
ELSE
// No safe load step found! Not good.
// Company needs to decide if unit should NOT be allowed to go ONLINE, or
// if they want to force a default load step to use instead.
CurrentLoadStep =
-1
ENDIF
Modbus.NumberOfDataValues = eRCM_CheckSafeStartUpLen
Modbus.Address = eRCM_CheckSafeStartUp
Modbus.Data(1) =
0 // The “0” tells eRCM Express to stop determining Safe
Start Up LS
Modbus.Write()
ELSE
// If we do not have access to final discharge pressure, then it is not clear
// which (if any) load step to implement to bring unit online safely. Thus,
// based on OEM, Operators, Engineering, the load step to use during closing
// of the Bypass Valve has been determined to be “ ??? ”. Thus, implement this
// step.
CurrentLoadStep =
23 // For Two-stage injection, use last load step, LS#23.
ENDIF