Dynasonics MFX Series Insertion MagProbe Flow Meter - Manual (Page 77)

bbc generation: the bbc byte is generated by summing without overflow all characters in the transmis-
sion prior to the bbc byte excluding the [:] The bbc byte is then subtracted from ffh and
added to 01h. The incoming bbc byte is compared to the calculated bbc.
NVD structure: The non-volatile data is contained in a data structure as listed below: Care must be
taken when presetting the NVD registers as there is no error checking involved in preset-
ting of these values. If improper data is supplied, the MFX may no longer function prop-
erly, or may cease to function completely.
union
{
structure
struct
{
char VELU[5];
char FRUnit[5];
char Cndx;
char Scale;
unsigned char rly2_code;
unsigned char rl21_code;
unsigned char time_code;
unsigned char unit_code;
unsigned int cal20;
unsigned int cal4;
unsigned int SP_Hi;
unsigned int SP_Lo;
unsigned int access_code;
float PRB_FACT;
float MIN_FLOW;
float MAX_FLOW;
float VEL_CODE;
float RLY2_LL;
float RLY1_LL;
float RLY2_HL;
float RLY1_HL;
float MFE;
float TIMECODE;
float UNITCODE;
float CUTOFF;
float P_ID;
float TOT;
};
unsigned char[82];
}NVD;
Non-volatile data is transferred one character at a time as the data is contained in memory.
The entire block must be received as a whole without error or else the transmission will be ig-
nored and an error code will be returned.
RS232 Communications Protocol
Software Version: 08-01-2000
Page: 2 of 2
RS232 COMMUNICATIONS PROTOCOL