System and method for maintaining synchronized data transfer using a plurality of different control words individually indicative of the same single event
A method and apparatus for the transmission of multiple control characters of the same type to a receiver to improve the retention of transmitter to receiver synchronization in a noisy environment having receiver code that is less complex and does not require an increase in the bandwidth of the system since the control codes are already utilized to initiate other functions. Detection of any of the control characters of the same type by the receiver allows the receiver to maintain proper synchronization. The receiver will detect these control signals and anticipate the occurrence of an event within a predetermined time period.
1. A data transfer system that maintains synchronized data transfer comprising:
a transmitter device configured to transmit at least data and a plurality of different control words across an interface, wherein the plurality of different control words are individually indicative of a same single event, and wherein at least one of the plurality of different control words is transmitted prior to the data or at least one of the plurality of different control words is transmitted subsequent to the data;
a receiver device operatively connected to said interface to receive the data and the plurality of different control words from said transmitter device;
an identification device within said receiver device that detects at least one of the plurality of different control words as indicative of the single event; and
a timing device within said receiver device for generating at least one time interval after detection of one of said plurality of different control words with respect to said single event;
wherein the identification device detects at least one of the plurality of different control words, such that detection of only one of the plurality of different control words is needed for acceptance of the received data.
2. The data transfer system of claim 1 , wherein said plurality of different control words recognized by said identification device further comprise at least two different start of line control words.
3. The data transfer system of claim 1 , wherein said plurality of different control words recognized by said identification device further comprise at least two different end of line control words.
4. The data transfer system of claim 1 , wherein said timing device further comprises a pulse generating circuit to indicate said single event.
5. The data transfer system of claim 1 , wherein said timing device can provide an individual time interval for each of said plurality of different control words.
6. The data transfer system of claim 1 , wherein each of said plurality of different control words has a predetermined spacing in relation to the data.
7. The data transfer system of claim 6 , wherein said timing device creates separate time intervals for each of said plurality of different control words in accordance with said predetermined spacing in relation to the data.
8. The data transfer system of claim 1 , wherein the plurality of different control words include at least three different control words each indicative of the single event.
9. A communication method for maintaining data synchronization comprising the steps of:
providing an interface from a transmitter to a receiver with said transmitter being configured to transmit at least data and a plurality of different control words across said interface and said receiver being operatively connected to said interface to receive the data and the plurality of different control words from said transmitter, wherein the plurality of different control words are individually indicative of a same single event, and wherein at least one of the plurality of different control words is transmitted prior to the data or at least one of the plurality of different control words is transmitted subsequent to the data;
forming an identification device within said receiver that recognizes at least one of the plurality of different control words transmitted across said interface as indicative of the single event;
sending the data and the plurality of different control words from said transmitter across said interface to said receiver such that a predetermined interval exists between each of said plurality of different control words and data; and
generating a timing signal after a predetermined time period after detection of one of said plurality of different control words;
wherein the identification device is formed such that recognition of only one of the plurality of different control words is needed for acceptance of the received data.
10. The method for maintaining data synchronization of claim 9 , wherein the step of forming further comprises said identification device being capable of recognizing at least two different start of line control words in the plurality of different control words.
11. The method for maintaining data synchronization of claim 9 , wherein the step of forming further comprises said identification device being capable of recognizing at least two different end of line control words in the plurality of different control words.
12. The method for maintaining data synchronization of claim 9 , wherein the step of generating a timing signal further comprises generating a timing signal after a predetermined time period after recognizing one of the plurality of different control words to indicate said single event.
13. The method for maintaining data synchronization of claim 9 , wherein the step of generating a timing signal further comprises generating a timing signal after a predetermined time period after recognizing one of the plurality of different control words, said predetermined time period being different depending upon which control word is recognized.
14. The method for maintaining data synchronization of claim 12 , wherein the single event is the completion of data transfer.
15. The method for maintaining data synchronization of claim 9 , further comprising the step of using said timing pulse signal to set a flag within said receiver.
16. The method for maintaining data synchronization of claim 9 , wherein the step of sending further comprises sending the data and the plurality of different control words such that said plurality of different control words have a first spaced relation to each other as well as a second spaced relation with respect to the data.
17. The method for maintaining data synchronization of claim 9 , wherein the step of sending further comprises sending characters across said interface such that at least one signal on said interface identifies characters as being either control characters or data characters.