parity | Shell commands for development , staging , and production

Is there generic practices and patterns to succesfully switch from dynamic to static memory allocation without breaking the code ?

No, not really. You'll have to rewrite all such code in pretty radical ways.

You have to realize why all safety-related and embedded systems ban malloc. The main reason is that it is non-deterministic. Instead of allowing completely variable sizes, you have to specify a maximum size for each such item, to cover the worst case scenario of the application.

Also, the presence of things like pointer-to-pointers instead of 2D arrays is a pretty certain indication that the original programmer didn't quite know what they were doing in the first place.

Additionally you need to drop the default types of C for stdint.h ones. That's standard practice in all embedded systems.

In general, I'd strongly advise to drop those "NASA rules" and implement MISRA-C instead. It's a way more professional and in-depth document. Some of the "NASA rules" simply don't make sense and the rest can be summarized as "No s***t Sherlock" beginner-level stuff which we were already told during our first beginner-level C programming class back in school. If these rules come as a surprise to someone, they shouldn't be writing mission-critical firmware in the first place.

The fact that the parity bit CAN be set is just an observation, not a generally followed protocol. That being said, I know of no programming languages that actually care about parity when decoding ASCII. If the highest bit is set, the number is simply treated as >=128, which is out of range of the known ASCII characters.

The device manual isn't clear about the register start address, but the first register it mentions has the address of 1.

Similarly, the mbpoll command-line utility (not the one with GUI) isn't very clear about the start address. But its documentation mentions that the default value for -r parameter is 1.

I think it's safe to assume that both use the same addressing which starts from 1, as the command-line tool has no problems accessing the value.

But MinimalModbus API clearly mentions that its register start address is 0. So when using this library, you need to use registeraddress = 45 for accessing the temperature, not 46 or 40046.

But why won't 46 work? Normally, one would expect it to grab data starting from the next register and print some garbage, but not timeout. But we can't know how the device works internally. Maybe a request to access the temperature register actually triggers some measurement function and then returns a value. A request to access an unaligned data (with a wrong register value) can be simply rejected by the firmware.

If you still get timeouts with registeraddress = 45, your Python runtime may have some problems accessing the serial port. As I stated in my comment, I recommend using a logic analyzer to see what's going on on the wire. Without such a tool, you're doing blind-debugging.

Your first line for the USART3 initialization is wrong :-)

RCC->APB2ENR |= 1; // enable clock for AF

must be (without a clock the USART doesn't work)

RCC->APB1ENR |= (1<<18); // enable clock for USART

And as an additional hint, do not use all these magic numbers for the bits. This is much more readable (and the needed defines are already done in the CMSIS:

RCC->APB1ENR |= RCC_APB1ENR_USART3EN; // enable clock for USART

From Intel's manual (section 3.4.3.1 Status Flags):

Parity flag — Set if the least-significant byte of the result contains an even number of 1 bits; cleared otherwise.

The least significant byte after DEC BX is 50h (i.e. 1010000b), which has an even number of ones. So you'll get PF=1.

Similarly, after the NEG, the least significant byte is B0h (10110000b), which has an odd number of ones. So you get PF=0.

The problem lies with

You can use apply to make the recursive calls without using a helper function. Its last argument is a list, which will be spread into arguments in the function call. This allows you to pass first again as well as (cdr lst).

You can also just use cons to build a new list from an element and a subsequent list, rather than creating a temporary list to use append-list.

the output from python is correct. bytes(integer) creates an array of provided size, all initialized to null in your case size = 1, bytes(1), so the output that you have is 0x00 if you try bytes(10) the out put will be b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'.

what you need to do is to change ser.write(bytes(1)) to ser.write(bytes('1',encoding= 'utf-8')) that should work

Your code is correct. You're getting the case column because of the augment(babies) call, but if you replace it with augment(babies %>% select(-case)) you wont get that column. In other words, the regression model you're fitting does not take into acount the case column].