# US 9,436,648 B2 · Method for matching the signal transmission between two electronic devices, and arrangement having a computer system and a peripheral device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,436,648 B2 - Document ID: US9436648B2 - Status: Granted - Kind: B2 - Application number: 13/883,029 - Filed: 2011-10-27 - Published: 2013-10-24 - Granted: 2016-09-06 - Earliest claimed: 2010-11-08 - Assignees: Fujitsu Limited - Applicants: Robert Depta - Inventors: Robert Depta - Web page: https://patentgrep.com/patent/US9436648B2 ## CPC - G06F 13/4291: {using a clocked protocol} - G06F 13/426: {using an embedded synchronisation, e.g. Firewire bus, Fibre Channel bus, SSA bus} - H04B 2203/5425: improving S/N by matching impedance, noise reduction, gain control - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - H04B: TRANSMISSION ## Abstract A method of matching signal transmission between two electronic devices connected to one another with a physical interface and each have a transmitter and a receiver, wherein signals are transmitted from the transmitter of one device along a transmission link to the receiver of the other device and wherein the transmission link has at least two signal lines (+, −) for differential transmission of the signals including A) detecting signal values on the receiver of the first device separately for each of the two signal lines (+, −), B) evaluating a mismatch between the signals from the two signal lines (+, −) on the receiver of the first device on the basis of the detected signal values, and C) changing one or more parameters of the transmitter in the second device for at least one of the two signal lines (+, −), wherein at least A) and C) are performed iteratively until a predetermined termination criterion is satisfied. ## Claims ### Claim 1 A method of matching signal transmission between two electronic devices connected to one another with a physical interface and each have a transmitter and a receiver, wherein signals are transmitted from the transmitter of one device along a transmission link to the receiver of the other device and wherein the transmission link has at least two signal lines (+, −) for differential transmission of the signals, comprising: A) detecting signal values on the receiver of the first device separately for each of the two signal lines (+, −), B) evaluating a mismatch between the signals from the two signal lines (+, −) on the receiver of the first device on the basis of the detected signal values, and C) changing one or more parameters of the transmitter in the second device separately and individually for the two individual signal lines (+, −) such that the signals on at least one of the two signal lines (+, −) are affirmatively provided with and subjected to imbalances in the transmitter of the second device prior to transmission, whereby after the transmission balanced signals from the two signal lines (+, −) are available on the receiver of the first device, wherein A), B) and C) are performed iteratively until a predetermined termination criterion is satisfied. ### Claim 2 (depends on 1) The method according to claim 1, wherein the predetermined termination criterion is a predetermined quantity of signal values, a particular magnitude of a result space, or reaching a predetermined close environment around the optimum for a mismatch between the signals from the two signal lines (+, −). ### Claim 3 (depends on 1) The method according to claim 1, wherein the parameters of the transmitter in the second device are matched such that properties of the signals from at least one of the two signal lines (+, −) are altered by the transmitter in the second device, as a result of which the mismatch between the signals from the two signal lines (+, −) can be reduced on the receiver. ### Claim 4 (depends on 3) The method according to claim 3, wherein the properties of the signals comprise at least: signal amplitude, edge gradient, pre-emphasis, initiation time and phase shift. ### Claim 5 (depends on 1) The method according to claim 1, performed automatically. ### Claim 6 (depends on 1) The method according to claim 1, wherein the detected signal values are transmitted to the second device and the mismatch is evaluated in the second device. ### Claim 7 (depends on 1) The method according to claim 1, wherein the mismatch is evaluated in the receiver of the first device and a result of the evaluation is transmitted to the second device. ### Claim 8 (depends on 6) The method according to claim 6, wherein the transmission to the second device is performed via a further data line separately from the signal lines (+, −). ### Claim 9 (depends on 1) The method according to claim 1, wherein a processing unit in the second device detects the mismatch and stipulates changed properties of the signals. ### Claim 10 (depends on 9) The method according to claim 9, wherein a matching unit in the second device requests the stipulated properties of the signals from the processing unit and calculates changed parameters of the transmitter in the second device. ### Claim 11 (depends on 10) The method according to claim 10, wherein the calculated parameters are stored in the settings register in the second device, and the transmitter is matched for signal transmission by using the parameters from the settings register. ### Claim 12 (depends on 1) An arrangement comprising a computer system and a peripheral device, wherein 1) the peripheral device connects to the computer system by a physical interface, 2) the computer system and the peripheral device each have a transmitter and a receiver that transmits signals between the computer system and the peripheral device, and 3) the arrangement is set up such that the transmitters of the computer system and the peripheral device are matched by a method according to claim 1. ### Claim 13 (depends on 12) The arrangement according to claim 12, wherein the computer system has a host bus adapter to which the peripheral device is connected. ### Claim 14 (depends on 12) The arrangement according to claim 12, wherein the physical interface is designed on the basis of one of the following standards: SCSI, SAS, SATA, Fiber Channel, USB. ### Claim 15 A method of matching signal transmission between two electronic devices connected to one another with a physical interface and each having a transmitter and a receiver, wherein signals are transmitted from the transmitter of one device along a transmission link to the receiver of the other device and wherein the transmission link has at least two signal lines (+, −) for differential transmission of the signals, comprising: A) detecting signal values on the receiver of the first device separately for each of the two signal lines (+, −), B) evaluating a mismatch between the signals from the two signal lines (+, −) on the receiver of the first device on the basis of the detected signal values, and C) changing one or more parameters of the transmitter in the second device for at least one of the two signal lines (+, −), wherein A), B) and C) are performed iteratively until a predetermined termination criterion is satisfied, the parameters of the transmitter in the second device are matched such that properties of the signals from at least one of the two signal lines (+, −) are altered by the transmitter in the second device as a result of which the mismatch between the signals from the two signal lines (+, −) can be reduced on the receiver, and the properties of the signals comprise at least: signal amplitude, edge gradient, pre-emphasis, initiation time and phase shift. ### Claim 16 A method of matching signal transmission between two electronic devices connected to one another with a physical interface and each having a transmitter and a receiver, wherein signals are transmitted from the transmitter of one device along a transmission link to the receiver of the other device and wherein the transmission link has at least two signal lines (+, −) for differential transmission of the signals, comprising: A) detecting signal values on the receiver of the first device separately for each of the two signal lines (+, −), B) evaluating a mismatch between the signals from the two signal lines (+, −) on the receiver of the first device on the basis of the detected signal values, and C) changing one or more parameters of the transmitter in the second device for at least one of the two signal lines (+, −), wherein A), B) and C) are performed iteratively until a predetermined termination criterion is satisfied, a processing unit in the second device detects the mismatch and stipulates changed properties of the signals, and a matching unit in the second device requests the stipulated properties of the signals from the processing unit and calculates changed parameters of the transmitter in the second device. ### Claim 17 (depends on 16) The method according to claim 16, wherein the calculated parameters are stored in a settings register in the second device, and the transmitter is matched for signal transmission by using the parameters from the settings register.