Ah, I see. I never pay attention to the tags; I guess I'm old fashioned, although I've heard about the existence of twitter already ;)
There's no "old" and "new" USB IP in the STM32 - there's the device-only (in 'F0/'L0/lower-end 'F1/lower-end 'L4/probably in 'L1 but I don't quite follow those); and there's the OTG, i.e. host+device+all-the-stuff-needed-to-switch-between-them-a.k.a.-OTG (in 'F2/'F4/higher-end 'F1/higher-end 'L4/'F7), this IP is bought from Synopsys and its roots may easily be much older than the device-only IPs.
The OTG module is much, much more complex than the device-only one, thus it occupies more silicon area. And, however it may sound weird, transistors still are not zero size and silicon area still determines ultimately the cost/price of the chip. There are also licencing costs/royalties involved with each module, plus other costs like support. Now which modules (and processor) is put into which model is a matter of tradeoff, based on the "target audience".
The Cortex-M23/M33 thus the 'L5 build upon the IoT buzz. And the audience is being intensely massaged by the message that IoT needs security (which is certainly true, even if nobody knows what IoT means) and that that security can be bought as a separate enclosed piece of software (which is certainly not true, but nobody who hears to the IoT buzz wants to know that) and 'M23 is designed to deliver that enclosure/separation in hardware.
As nobody knows what IoT means, almost anything can be sold under that moniker; but the currently most sellable idea is that of the connected fridge. It means, a gadget, which in itself doesn't need any connectivity, but the rich west (and I'm saying this as a relatively rich west-ish type) can afford useless gadgets as another means to justify their otherwise rather useless other gadgets called for some weird historical reasons mobile phones (weird, as they don't primarily serve the purpose of telephoning anymore). The IoT gadgets have to be sold expensively but built cheaply, so the chips in them can't contain modules which would add another halfdollar or so to their price; and I bet even the rich westerner would question the purpose of a fridge which can autonomously print or write logfiles to an USB thumbdrive.
But, if the idea of packagable security catches on - and it's likely to catch on as it sells on the "you don't need to learn it" idea which is popular these days - I bet we'll see higher-end 'L5s in the future with the OTG module, just wait for it.
JW
