System for setting frame and protocol for transmission in a UART device

• US 6,678,751 B1
• Filed: 05/12/2000
• Issued: 01/13/2004
• Est. Priority Date: 10/15/1999
• Status: Expired due to Term

• Current Assignee: Micro Motion Incorporated (Emerson Electric Company)
• Original Assignee: Micro Motion Incorporated (Emerson Electric Company)
• Inventors: Hays, Paul J., Mansfield, William M.
• Primary Examiner(s): Perveen, Rehana
• Application Number:
  US09/569,657
• Time in Patent Office: 1,341 Days
• Field of Search: 710/8, 710/14, 710/33, 710/60, 709/217, 709/227, 709/228
• US Class Current: 710/8
• CPC Class Codes: H04L 25/0262 Arrangements for detecting the data rate of an incoming signal

Abstract

A system for setting baud rate and communication protocol in a remote device. In this invention, the remote device receives samples of signals from a host device in a buffer. The remote device then detects a baud rate of said signals from the samples. A protocol being used by the host device to communicate is also determined from the samples. The remote device is then set to communicate using the determined protocol at the detected baud rate.

Claims

1. A method for a remote device to establish communication with a host device, the method comprising the steps of:

receiving samples of signals from said host device in a buffer;

detecting a baud rate of said signals from said samples;

determining from said samples a protocol being used by said host device to communicate by performing protocol template matching between said samples and templates of known bits in supported protocols, said step of performing protocol template matching comprising;

reading one of a plurality of protocol templates,

reading said samples of said signals from said buffer,

comparing said one of said plurality of protocol templates to said samples of said signals, and

determining said signals are being transmitted in a protocol of said one of said plurality of protocol templates responsive to a match of said one of said plurality of protocol templates and said samples of said signals; and

setting said remote device to communicate with said host device using said determined protocol at said detected baud rate.

2. The method of claim 1 wherein said step of detecting said baud rate comprises the step of:

determining whether a level transition between two bits is received within a certain number of said samples.

3. The method of claim 2 wherein said step of detecting further comprises the step of:

adjusting a sample rate responsive to said level transition between two bits not being received within said certain number of samples.

4. The method of claim 2 wherein said step of detecting further comprises the step of:

determining said baud rate is less than or equal to n divided by 8 responsive to a determination that said level transition between two bits is not received within said certain number of said samples.

5. The method of claim 4 wherein said step of performing protocol template matching comprises the step of:

performing said protocol template matching for baud rates of n divided 8 and less responsive to a determination that said baud rate is less than or equal to n divided by 8.

6. The method of claim 2 wherein said step of detecting further comprises the step of:

determining said baud rate is between n and n/4 responsive to a determination that said level transition between two bits is not received within said certain number of said samples.

7. The method of claim 6 wherein said step of performing protocol template matching comprises the step of:

performing said protocol template matching for baud rates between n and n/4.

8. An apparatus in a remote device for establishing communication with a host device, said apparatus comprising;

means for receiving samples of signals from said host device;

means for storing said samples;

means for detecting a baud rate of said signals from said samples;

means for determining from said samples a protocol being used by said host device to communicate by performing protocol template matching between said samples and templates of known bits in each supported protocol, said means for determining from said samples a protocol comprising;

means for reading one of a plurality of protocol templates,

means for reading said samples of said signals from said buffer,

means for comparing said one of said plurality of protocol templates to said samples of said signals, and

means for determining said signals are being transmitted in a protocol of said one of said plurality of protocol templates responsive to a match of said one of said plurality of protocol templates and said samples of said signals; and

means for setting said remote device to communicate with said host system using said determined protocol at said detected baud rate.

9. The apparatus of claim 8 wherein said means for detecting said baud rate comprises:

means for determining whether a level transition between two bits is received within a certain number of said samples.

10. The apparatus of claim 9 wherein said means for detecting further comprises:

means for adjusting a sample rate responsive to said level transition between two bits not being received within said certain number of said samples.

11. The apparatus of claim 9 wherein said means for detecting further comprises:

means for determining said baud rate is less than or equal to n divided by 8 responsive to a determination that said level transition between two bits is not received within said certain number of said samples.

12. The apparatus of claim 11 further comprising:

means for performing said protocol template matching for baud rates of n divided 8 and less responsive to a determination that said baud rate is less than or equal to n divided by 8.

13. The apparatus of claim 9 wherein said means for detecting further comprises:

means for determining said baud rate is n and n/4 responsive to a determination that said level transition between two bits is not received within said certain number of said samples.

14. The apparatus of claim 13 wherein said means for determining from said samples a protocol comprises:

means for performing said protocol template matching for each supported baud rate between n and n/4.

15. A product that allows a remote device to establish communication with a host device, the product comprising:

a media readable by a processor to store instructions; and

said instructions for directing said processor in said remote device to;

receive samples of signals from said host device,

detect a baud rate of said signals from said samples,

determine from said samples a protocol being used by said host device to communicate by performing protocol template matching between said samples and templates of known bits in each supported protocol, and

set said remote device to communicate with said host device using said determined protocol at said detected baud rate;

said instructions perform said protocol template matching by directing said processor to;

read one of a plurality of protocol templates,

read said samples of said signals from said buffer,

compare said one of said plurality of protocol templates to said samples of said signals, and

determine said signals are being transmitted in a protocol of said one of said plurality of protocol templates responsive to a match of said one of said plurality of protocol templates and said samples of said signals.

16. The product of claim 15 wherein said instructions to detect said baud rate comprise:

instructions for directing said processor to determine whether a level transition between two bits is received within a certain number of said samples.

17. The product of claim 16 wherein said instructions to detect said baud rate further comprise:

instructions for directing said processor to adjust a sample rate responsive to said level transition between two bits not being received within said certain number of said samples.

18. The product of claim 16 wherein said instructions to detect said baud rate further comprise:

instructions for directing said processor to determine said baud rate is less than or equal to n divided by 8 responsive to a determination that said level transition between two bits is not received within said certain number of said samples.

19. The product of claim 18 wherein said instructions to determine from said samples a protocol further comprise:

instructions for directing said processor to perform said protocol template matching for baud rates of n divided by 8 and less responsive to a determination that said baud rate is less than or equal to n divided by 8.

20. The product of claim 16 wherein said instructions to detect said baud rate further comprise:

instructions to determine said baud rate is between n and n/4 responsive to a determination that said level transition between two bits is not received within said certain number of said samples.

21. The product of claim 20 wherein said instructions to determine from said samples a protocol comprise:

instructions to perform said protocol template matching for each supported baud rate between n and n/4.