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Emulated terminals can accept control characters, being able to move the position of cursor, to delete a char or a word or even to clear all screen, change foreground and background colors, etc. oriented by them.
Question: Originally (that means for real terminal teletypes), these characters controls were handle by the output device or managed directly by CPU (for example, via related routines monitoring output data sending to such device and working over it)?
For actual Teletypes, which are electromechanical devices whose output is ink on paper, there were these ways to move the print position (there was no actual cursor):
Carriage return: mechanically move typehead to column 1.
Line feed: mechanically roll the paper
Any printing character: move one place to the right after printing
From memory, I don't think an ASR 33 could implement tab or backspace. Tab expansion would be done on the host machine. Backspace probably would not be done at all, though I suppose you could simulate it with return and a lot of spaces (but for what point?)
So, with the exception of tab, neither device nor computer would implement any extra movement operations: it was simply not possible.
Other control characters:
BEL rang a bell.
XON/XOFF were used to enable or disable an attached papertape reader.
I think that's about it for the control-character repertoire.
There were no general cursor-movement sequences because the hardware could not do those things.
In case you also include other serial CRT devices, sometimes referred to as "glass teletypes", then the answer is often the same as for emulators: there's something in there, at least from the mid-1970s likely to be a simple microprocessor, interpreting the character stream and doing what the control sequences tell it to do.
But note that not all glass teletypes implemented 'direct cursor addressing' capabilities. Early/cheap terminals were functionally the same as actual teletypes.
ul command. It also had switchable type trays (immortalized in such things as the BSD greek command) and (according to the advert on page 932 of ISBN 9781483160238) software-settable vertical and horizontal tabstops (and thus vertical and horizontal tab).
Teletypes were self contained units simply executing the code received. For most codes that simply meant printing a certain character and advance by one position. Others
All of this was done by mechanics using levers, spoke wheels, combs and rods (*1).
There is no controlling CPU. TTYs were meant to work with other TTY, not computers/CPUs. They only later on repurposed TTY as terminals.
*1 - IoT before the internet - process control by things moving:)
Real teletypes were pure electromechanical devices with no CPU, or any electronic components at all. On receiving a line feed code the paper was advanced a line or with a carriage return the printing carriage was brought to the leftmost position. All of this was done purely by electrical and mechanical operations.
Early teletype machines were in use as early as the mid 19th century, long before the development of the electronic computer. My first experience with them was in the 1970's. These were mostly the traditional mechanical printing devices but thermal printing was being introduced. These early devices did not have a CPU.
