Choosing a transport protocol
The main issue with choosing a transport protocol is this:
What do you want to happen when a packet is lost/corrupted?
USE TCP If you want the protocol stack to fix it for you invisibly, you will increase jitter (TCP will time out and retransmit)
You can use an open/close per sample (simple but quite a lot of traffic)
The datasheet states that the power supply range is from 2.4V to 3.6V.
The included brownout detection circuit triggers a warning interrupt
below 2.2V and asserts the Reset below 1.85V.
At first glance this appears to be silly. What is the point of having a brownout voltage set below the minimum operating voltage of the chip?
However the datasheet also ...
I'd seriously look into mqtt/udp. From the description of your project any old hack likely would work, but by using something like mqtt/udp your code/project would be reusable for other more sophisticated projects.
If you want this to run on a really, really small processor you may be able to reduce your network/...
The MEM functios can directly read and write devices that have register address based access. They write the register addresss before reading or writing the register data. Most chips are like this. The non-MEM functions just do simple reads and writes.
A number of SPI slaves can be connected in one of two configurations:
Single Slave-Select daisy-chained
Here the entire SPI bus is treated as one big shift register and the master must know the order of devices in the bus chain and their respective register widths. It is also necessary to write all devices at the same time in the same bus transaction. ...
Have you enabled the Clock for the Power Module?
It is kind of confusing that you have to enable something to reduce the power consumption.
Deactivating all clocks of unused Peripherals will also lead to a major power reduction.
We also measure higher current consumption while the controller is still connected to a debugger.
From the user manual:
Please note the typical definitions (emphasis mine):
What is missing is the characterization of the BOD module.
The LPC176x/5x includes a Brown-Out Detector (BOD) that provides
2-stage monitoring of the voltage on the VDD(REG)(3V3) pins. If this
voltage falls below the BOD interrupt trip level (typically 2.2 V
under nominal ...