초록 ▼

Dynamic baselining of current modulation-based talkback from a slave device to a master device in a system such as an electronic blasting system, wherein the dynamic baselining enhances communication integrity under conditions of environmental noise and the like. With a data packet of appreciable le

Dynamic baselining of current modulation-based talkback from a slave device to a master device in a system such as an electronic blasting system, wherein the dynamic baselining enhances communication integrity under conditions of environmental noise and the like. With a data packet of appreciable length, the dynamic baselining is preferably performed repeatedly on the bytes or words within the packet.

대표청구항 ▼

What is claimed is: 1. A method of dynamically baselining current modulation-based talkback comprising the following steps: a) establishing an electrically-connected system that includes a master device and at least one slave device that communicates to the master device using current modulation-ba

What is claimed is: 1. A method of dynamically baselining current modulation-based talkback comprising the following steps: a) establishing an electrically-connected system that includes a master device and at least one slave device that communicates to the master device using current modulation-based talkback; b) causing said master device to periodically measure a baseline level of the talkback current; and, c) causing said master device to thereafter receive talkback compensated according to said measured baseline level of talkback current. 2. The method of claim 1, wherein said slave device includes an explosive. 3. The method of claim 1, wherein step b) includes the step of measuring a baseline level of the digital low value of said talkback. 4. The method of claim 3, wherein said slave device includes an explosive. 5. The method of claim 1, wherein said current modulation-based talkback includes a serial packet comprising multiple command/data words, and the measurement of step b) is performed at least once for each command/data word. 6. The method of claim 5, wherein said current modulation-based talkback includes a serial packet that in which a four-bit synchronization sequence "0101" is included with each command/data word, and the measurement of step b) is performed on one or more of said synchronization sequences. 7. The method of claim 1, wherein said current modulation-based talkback includes a serial packet that includes a plurality of synchronization bits, and the measurement of step b) is performed on one or more of said synchronization bits. 8. An electrically-connected system for dynamically baselining current modulation-based talkback comprising: a) a master device; and, b) at least one slave device configured to transmit data to said master device through current modulation-based talkback; wherein the system is configured such that the master device periodically measures a baseline level of the talkback current and thereafter receives talkback compensated according to said measured baseline level. 9. The system of claim 8, further including a bus having a high voltage and a low voltage, wherein said slave device is configured to transmit data to said master device through current modulation-based talkback while said master device holds said bus at said low voltage. 10. The system of claim 8, wherein the system is configured such that the master device periodically measures a baseline level of the digital low value of the talkback current. 11. The system of claim 10, further including a bus having a high voltage and a low voltage, wherein said slave device is configured to transmit data to said master device through current modulation-based talkback while said master device holds said bus at said low voltage. 12. The system of claim 8, wherein said current modulation-based talkback includes a serial packet comprising multiple command/data words, and wherein the system is configured such that said master device performs said periodic baseline measurement at least once for each command/data word. 13. The system of claim 12, wherein said current modulation-based talkback includes a serial packet that includes a plurality of synchronization bits, and wherein the system is configured such that said master device performs said periodic baseline measurement on one or more of said synchronization bits. 14. The system of claim 8, wherein said current modulation-based talkback includes a serial packet that includes a plurality of synchronization bits, and wherein the system is configured such that said master device performs said periodic baseline measurement on one or more of said synchronization bits. 15. A master device for use in an electrically connected system including at least one slave device that communicates with said master device through current modulation-based talkback, wherein said master device is configured to periodically measure a baseline level of the talkback current and thereafter receive talkback compensated according to said measured baseline level. 16. The master device of claim 15, wherein said master device is configured to receive said talkback over a bus having a high voltage and a low voltage, and said master device is further configured to hold said bus at said low voltage during said talkback. 17. The master device of claim 15, wherein said master device is configured to periodically measure a baseline level of the digital low value of the talkback current. 18. The master device of claim 15, wherein said current modulation-based talkback includes a serial packet comprising multiple command/data words, and wherein said master device is configured to perform said periodic baseline measurement at least once for each command/data word. 19. The master device of claim 15, wherein said current modulation-based talkback includes a serial packet that includes a plurality of synchronization bits, and wherein said master device is configured to perform said periodic baseline measurement on one or more of said synchronization bits. 20. The master device of claim 15, wherein said master device is configured with an A/D converter or comparator algorithm.