Command 1F Cancel Request

Command $1F is the "cancel" command. It has the following format:

• byte 1F: mtype
• byte 05: fixed length
• dword: nonce
• byte with bits AAAA0BCD: AAAA is a 4-bit value while bits B, C, and D select the case.

The B bit being set will turn off the RR reminders variables set from the $13 Basal Schedule command and some other variables presumably related to the basal rate. The C bit being set will turn off the RR reminder variables set from the $16 Temp Basal command and some other variables presumably related to a temporary basal rate. The D bit being set will turn off the RR reminder variables set from the $17 Bolus Extra command and some other variables presumably related to a bolus.

The Pod responds to the $1F command with a $1D status message.

An example from Temp Basal Packets: 1f05 d88df895 62

A cancel is also done as part of Deactivate Pod, apparently canceling all three cases: 1f05 e1f78752 07

Suspend

The $1F command is also used for "suspend". Currently omni_listen_rfcat is not outputting the suspend command from the PDM, just the response from the POD. Used rtlomni to capture the transaction though: 1f108958a11f10895800030e010000220e, which looks like another variation of the cancel command.

Resume:

2017-11-17T15:00:58.382990 ID1:1f068f54 PTYPE:PDM SEQ:28 ID2:1f068f54 B9:a0 BLEN:58 BODY:1a168fa118cf0001f21d01400000b806900af0095009300713 CRC:d3

Cancel Temp Basal

Another variation of the $1F command is the cancel temp basal command.

2017-10-04T14:37:13.979405 ID1:1f0b3555 PTYPE:PDM SEQ:23 ID2:1f0b3555 B9:08 BLEN:7 BODY:1f05156b93e8620028 CRC:35
2017-10-04T14:37:14.307150 ID1:1f0b3555 PTYPE:PDM SEQ:23 ID2:1f0b3555 B9:08 BLEN:7 BODY:1f05156b93e8620028 CRC:35
2017-10-04T14:37:14.377525 ID1:1f0b3555 PTYPE:POD SEQ:24 ID2:1f0b3555 B9:0c BLEN:10 BODY:1d1800251000000063ff82bb CRC:91
2017-10-04T14:37:14.378063 ID1:1f0b3555 PTYPE:ACK SEQ:25 ID2:1f0b3555 CRC:f0

Cancel Insulin Delivery

Yet, another $1F command variation is to bolus certain amount and then cancel half way through. The PDM reports the partially delivered amount.

2017-11-17T15:07:17.702593 ID1:1f068f54 PTYPE:PDM SEQ:17 ID2:1f068f54 B9:08 BLEN:7 BODY:1f053b9a70286401c0 CRC:2c
2017-11-17T15:07:17.737905 ID1:1f068f54 PTYPE:POD SEQ:18 ID2:1f068f54 B9:0c BLEN:10 BODY:1d1800d610010007dfff803b CRC:87
2017-11-17T15:07:18.143485 ID1:1f068f54 PTYPE:ACK SEQ:19 ID2:1f068f54 CRC:33
2017-11-17T15:07:22.162888 ID1:1f068f54 PTYPE:PDM SEQ:20 ID2:1f068f54 B9:10 BLEN:3 BODY:0e01000110 CRC:f7
2017-11-17T15:07:22.236193 ID1:1f068f54 PTYPE:POD SEQ:21 ID2:1f068f54 B9:14 BLEN:10 BODY:1d1800d610010007dfff02b5 CRC:d3