Issue link: https://read.uberflip.com/i/1428395
LoRaWAN ® L2 1.0.4 Specification © 2020 LoRa Alliance ® Page 34 of 90 The authors reserve the right to change specifications without notice. 1055 The RX1 data-rate offset (RX1DROffset) field sets the offset between the uplink data rate 1056 and the downlink data rate used to communicate with the end-device on RX1. The default 1057 offset is 0. The offset takes into account the maximum power density constraints for gateways 1058 in some regions and balances the uplink and downlink radio link margins. 1059 The RX data rate (RX2DataRate) field defines the data rate of a downlink using the second 1060 receive window following the same convention as the LinkADRReq command. For example, 1061 0 means DR0/125 kHz. The frequency (Frequency) field corresponds to the frequency of 1062 the channel used for the second receive window, whereby the frequency is coded following 1063 the convention defined in the NewChannelReq command. 1064 The RXParamSetupAns command SHALL be used by the end-device to acknowledge the 1065 receipt of a RXParamSetupReq command. The RXParamSetupAns command SHALL be 1066 added in the FOpts field (if FPort is either missing or >0) or in the FRMPayload field (if 1067 FPort=0) of all uplinks until a Class A downlink is received by the end-device. This 1068 guarantees that, even in the case of an uplink frame loss, the Network is always aware of the 1069 downlink parameters used by the end-device. 1070 Following the transmission of a RXParamSetupReq command that modifies RX2 1071 (Frequency or RX2DataRate fields), the Network Server SHALL NOT transmit a Class C 1072 downlink before it has received a valid uplink frame containing RXParamSetupAns. 1073 1074 Note: An end-device that expects to receive Class C downlink frames 1075 will send an uplink frame as soon as possible after receiving a valid 1076 RXParamSetupReq that modifies RX2 (Frequency or RX2DataRate 1077 fields). 1078 1079 The payload contains a single Status octet. 1080 1081 Size (octets) 1 RXParamSetupAns payload Status Table 28: RXParamSetupAns payload format 1082 1083 1084 The status (Status) bits have the following meaning: 1085 1086 1087 Bits 7:3 2 1 0 Status RFU RX1DROffsetACK RX2DataRateACK ChannelACK Table 29: Status field format 1088 1089 1090