Method and system for error correction using asynchronous digital facsimile protocol

• US 5,440,405 A
• Filed: 07/21/1993
• Issued: 08/08/1995
• Est. Priority Date: 09/02/1992
• Status: Expired due to Term

• Current Assignee: Ricoh Company Limited, Ricoh Corporation (Ricoh Company Limited)
• Original Assignee: Ricoh Company Limited, Ricoh Corporation (Ricoh Company Limited)
• Inventors: Ahmed, Allam Z.
• Primary Examiner(s): Ro, Bentsu
• Application Number:
  US08/095,292
• Time in Patent Office: 748 Days
• Field of Search: 358/405, 358/434, 358/435, 358/436, 358/438, 358/439
• US Class Current: 358/435
• CPC Class Codes: H04N 1/3333 during transmission, input or output of the picture signal; within a single document or page
• CPC Class Codes: H04N 2201/33321 Image or page size, e.g. A3, A4
• CPC Class Codes: H04N 2201/33328 Resolution
• CPC Class Codes: H04N 2201/33357 Compression mode

Abstract

Communication system and method including a calling apparatus and a called apparatus. The system comprises handshake means for exchanging negotiation information including error correction ECM capabilities data, contained in a plurality of command frames between the calling apparatus and the called apparatus. The system further includes means for initiating an error correction operation, a transmitter for transmitting and receiving between the calling and the called apparatus a data set having associated data frame identification information, and verification means for verifying receipt of the data set. A method corresponding to the system also is described.

Claims

1. A method for operating a communication system, including a calling apparatus and a called apparatus, for transmitting data therebetween over an asynchronous digital network during a transmitting process in accordance with a protocol standard, wherein the calling apparatus and the called apparatus generate a plurality of command frames and at least one data frame during the transmitting process, the method comprising the sequential steps of:

(a) exchanging, between the calling apparatus and the called apparatus, a plurality of preliminary command frames representative of handshake protocol information including error correction method ECM capabilities;

(b) initiating an error correcting operation;

(c) transmitting a data set, including at least one data frame having associated data frame identification information, between the calling apparatus and the called apparatus; and

(d) verifying receipt of the data set.

2. The method of claim 1, wherein the exchanging step further comprises:

(i) transmitting a first command frame, including data representative of calling apparatus identification information, and a second command frame, including data representative of error correction method ECM information, from the calling apparatus to the called apparatus; and

(ii) transmitting a third command frame, including data representative of called apparatus identification information, and a fourth command frame, including data representative of error correction method ECM information, from the called apparatus to the calling apparatus.

3. The method of claim 1, wherein the verifying step further comprises transmitting, from the called apparatus to the calling apparatus, a command frame representative of end of page detect EDT including an end of page query.

4. The method of claim 1, wherein the verifying step further comprises transmitting, from the called apparatus to the calling apparatus, a command frame representative of partial page request PPR data including at least one data frame identification information associated with a data frame to be retransmitted from the data set.

5. The method of claim 1, wherein at least one transmission parameter is changed the method further comprising the step of transmitting a command frame representative of request next command RQN data including a request for transmission of the data set.

6. The method of claim 1, wherein the protocol standard defines a normal operation mode and a polling operation mode, the method further comprising the step of determining an operation mode for the transmitting process.

7. The method of claim 6, wherein the protocol standard is a polling operation mode, the transmitting step further comprising transmitting a data set, including at least one data frame having associated data frame identification information, from the called apparatus to the calling apparatus.

8. The method of claim 6, wherein the protocol standard is a normal operation mode, the transmitting step further comprising transmitting a data set, including at least one data frame having associated data frame identification information, from the calling apparatus to the called apparatus.

9. A communication system, including a calling apparatus and a called apparatus, for transmitting data therebetween over an asynchronous digital network during a transmitting process in accordance with a protocol standard, wherein the calling apparatus and the called apparatus generate a plurality of command frames and at least one data frame during the transmitting process, the system comprising:

(a) handshake means for exchanging a plurality of preliminary command frames, including error correction method ECM capabilities data, between the calling apparatus and the called apparatus;

(b) means for initiating an error correction operation;

(c) a transmitter for transmitting a data set, including at least one data frame having associated data frame identification information, between the calling apparatus and the called apparatus; and

(d) verification means for verifying receipt of the data set.

10. The system of claim 9, further comprising:

(i) means for transmitting a first command frame, including data representative of calling apparatus identification information, and a second command frame, including data representative of error correction method ECM information, from the calling apparatus to the called apparatus; and

(ii) means for transmitting a third command frame, including data representative of called apparatus identification information, and a fourth command frame, including data representative of error correction method ECM information, from the called apparatus to the calling apparatus.

11. The system of claim 9, further comprising means for transmitting, from the called apparatus to the calling apparatus, a command frame representative of end of page detect EDT including an end of page query.

12. The system of claim 9, further comprising means for transmitting, from the called apparatus to the calling apparatus, a command frame representative of partial page request PPR data including at least one data frame identification information associated with a data frame to be retransmitted from the data set.

13. The system of claim 9, wherein at least one transmission parameter is changed, the system further comprising means for transmitting a command frame representative of request next command RQN data including a request for transmission of the data set.

14. The system of claim 9, wherein the protocol standard defines a normal operation mode and a polling operation mode, the system further comprising means for determining an operation mode for the transmitting process.

15. The system of claim 14, wherein the protocol standard is a polling operation mode, the system further comprising means for transmitting a data set, including at least one data frame having associated data frame identification information, from the called apparatus to the calling apparatus.

16. The system of claim 14, wherein the protocol standard is a normal operation mode, the system further comprising means for transmitting a data set, including at least one data frame having associated data frame identification information, from the calling apparatus to the called apparatus.