3 - 16Auxiliary Port Input CommunicationsProtocol SelectionThis selection programs the Auxiliary Port for the protocol required by the inputdevice to the Auxiliary Port. The protocol is a set of rules concerning theexchange of data between serially communicating devices. The Auxiliary Portsupports Record, Burst, and ACK/NAK protocols when receiving data from anRS-232 device.When the Aux Port is being used as an input, data packets can be sent from theperipheral to the Aux Port in two different forms (See "Data CharacterSelection" on page 3-17).• Record -- a single string of data that is to be sent to the host system.• Block -- several strings of data that are to be appended together within thebase and sent to the host system as a single message.The programmer should determine which of the four selections below best meetsthe requirements of the peripheral.• Record -- used when the transmitting peripheral is sending messageswhen no confirmation of receipt is required.• Record ACK/NAK -- same as Record, however the base responds to theperipheral upon receipt of the message. The <ACK> (acknowledge)character (ASCII 06 hex) is sent to the peripheral to acknowledge that a<NAK> (non-acknowledge) character (ASCII 15 hex) is sent when themessage is not received correctly.• Block ACK/NAK -- same as Record ACK/NAK, but the <ACK> or <NAK>is issued upon completion of the block message.• Burst -- used when XON/XOFF software flow control is required by thetransmitting peripheral.*RecordBurstRecord ACK/NAKBlock ACK/NAK
