# US 8,543,802 B2 · Booting in systems having devices coupled in a chained configuration > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,543,802 B2 - Document ID: US8543802B2 - Status: Granted - Kind: B2 - Application number: 13/559,162 - Filed: 2012-07-26 - Published: 2012-11-15 - Granted: 2013-09-24 - Earliest claimed: 2009-08-21 - Assignees: Micron Technology, Inc. - Applicants: William H. Radke; Victor Y. Tsai; Peter Feeley; Neal A. Galbo; Robert N. Leibowitz - Inventors: William H. Radke; Victor Y. Tsai; Peter Feeley; Neal A. Galbo; Robert N. Leibowitz - Web page: https://patentgrep.com/patent/US8543802B2 ## CPC - G06F 9/4411: {Configuring for operating with peripheral devices; Loading of device drivers} - G06F 9/4401: Bootstrapping (security arrangements therefor G06F21/57) - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract The present disclosure includes methods, devices, and systems for booting in systems having devices coupled in a chained configuration. One or more embodiments include a host and a number of devices coupled to the host in a chained configuration, wherein at least one of the number of devices is a bootable device and the at least one bootable device is not directly coupled to the host. ## Claims ### Claim 1 A device, comprising: boot code, wherein: the device is configured to be coupled to a host in a chained configuration of devices; and the device is configured to send the boot code to the host through the chained configuration without receiving a boot command from the host. ### Claim 2 (depends on 1) The device of claim 1, wherein the device is configured to be coupled to the host in the chained configuration of devices such that the device is not directly coupled to the host. ### Claim 3 (depends on 1) The device of claim 1, wherein the device is configured to send the boot code to the host responsive to an event of the device. ### Claim 4 (depends on 3) The device of claim 3, wherein the event of the device is a power-on of the device. ### Claim 5 (depends on 3) The device of claim 3, wherein the event of the device is a reset of the device. ### Claim 6 A method for operating a device, comprising: sending, via the device, boot code to a host without receiving a boot command from the host; wherein the device is coupled to the host via a number of additional devices in a chained configuration. ### Claim 7 (depends on 6) The method of claim 6, wherein the method includes automatically sending, via the device, the boot code to the host responsive to a booting event of the device. ### Claim 8 (depends on 6) The method of claim 6, wherein sending the boot code to the host includes: sending the boot code from the device to one of the number of additional devices in the chained configuration; and sending the boot code from the one of the number of additional devices to the host. ### Claim 9 (depends on 6) The method of claim 6, wherein sending the boot code to the host includes sending the boot code to a pre-defined location in a memory of the host. ### Claim 10 A system, comprising: a host; and a number of devices coupled to the host in a chained configuration, wherein: at least one of the number of devices is a bootable device; and the host is aware of which of the number of devices is the at least one bootable device before sending a boot command to any of the number of devices. ### Claim 11 (depends on 10) The system of claim 10, wherein the at least one bootable device is not directly coupled to the host. ### Claim 12 (depends on 10) The system of claim 10, wherein: at least one of the number of devices is a pass-through device directly coupled to the host; and the bootable device is directly coupled to the pass-through device. ### Claim 13 (depends on 12) The system of claim 12, wherein the pass-through device is configured to: send data and instructions received from the host to the bootable device; and send data and instructions received from the bootable device to the host. ### Claim 14 (depends on 10) The system of claim 10, wherein: the at least one bootable device is associated with a default device identifier identifying that the at least one bootable device is the at least one bootable device; and the host is aware that the at least one bootable device is associated with the default device identifier before sending a boot command to any of the number of devices. ### Claim 15 (depends on 10) The system of claim 10, wherein the at least one bootable device includes boot code for the system. ### Claim 16 A method for operating a system, comprising: sending a boot command from a host to a number of devices coupled to the host in a chained configuration, wherein: at least one of the number of devices includes boot code for the system; and the host is aware of which of the number of devices include the boot code before sending the boot command. ### Claim 17 (depends on 16) The method of claim 16, wherein the method includes sending the boot code to the host responsive to receipt of the boot command by the at least one of the number of devices that includes the boot code. ### Claim 18 (depends on 17) The method of claim 17, wherein the boot command includes a location in a memory of the host to which the boot code is to be sent. ### Claim 19 (depends on 16) The method of claim 16, wherein the boot command includes: a default device identifier associated with the at least one of the number of devices that includes the boot code identifying that the at least one of the number of devices includes the boot code; and a command for the at least one of the number of devices that includes the boot code to send the boot code to the host. ### Claim 20 (depends on 16) The method of claim 16, wherein the boot command includes: a location in the at least one of the number of devices that includes the boot code where the boot code is located; and an amount of data included in the boot code. ### Claim 21 A system, comprising: a host; and a number of memory devices coupled to the host in a chained configuration, wherein: at least one of the number of memory devices is a bootable memory device configured to send boot code to the host without receiving a boot command from the host; and the at least one bootable memory devices is not directly coupled to the host. ### Claim 22 (depends on 21) The system of claim 21, wherein the number of memory devices coupled to the host in the chained configuration include: a first memory device directly coupled to the host; a second memory device directly coupled to the first memory device, wherein the second memory device is the bootable memory device. ### Claim 23 (depends on 22) The system of claim 22, wherein the first memory device and the second memory device are at least one of a dynamic random access memory (DRAM) device and a flash memory device.