Program Interface Library AR_GETWORDCEI-100/CEI-200/CEI-x20 User’s Manual 99AR_GETWORDCEI_INT16 ar_getword (CEI_INT16 board, CEI_INT16 channel,CEI_INT32 *destination);This routine gets the next available 32-bit ARINC word from the requestedchannel's buffer and puts it in the desired destination. If this routinesuccessfully returns a word (status is ARS_GOTDATA), there may or maynot be more words in the buffer. This function removes the data from thebuffer and writes it in the specified destination.Subsequent calls are required to determine if more words are in the buffer.When it returns ARS_NODATA, the buffer is empty. This is a circularFIFO buffer that is constantly being maintained by the ARINC interface asdata comes in. The data returned into “*destination” depends on thechannel type as follows:ARINC 429 Receiver Buffer Data FormatAll ARINC 429 receivers return data in the following format:Table 40. ARINC 429 Receive buffer31 - 8 7 - 0Data (MSB-LSB) Label (MSB-LSB)Per ARINC convention, the label is transmitted (MSB-first) followed bythe data (LSB-first). The API and the board hardware operateexclusively on engineering-formatted data.ARINC 573/717 Receiver Buffer Data FormatTable 41. ARINC 573/717 Receive Buffer31 – 16 15 14 13 - 12 11 - 0Time Tag insertedby firmwareSync WordFlag0 = data1 = syncX Sub Frame Data (MSB-LSB)SyntaxDescriptionNote:Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com
