Similar to https://stackoverflow.com/questions/978189/what-is-the-best-c-compiler-for-the-8051-family but with extended support for 251.
Keil have a solution, but it's $3k. For us that investment will never be repaid.
Has anyone had success extending SDCC for such a device? Unofficial gcc backend port?
Specifically, the core I'm trying to support is 80251 Typhoon from Dolphin Integration.
Current solutions I've found:
SmartCC80251 https://www.dolphin-integration.com/index.php/newsroom/news/313 (ROM pricing TBA) (just found this, wasn't easy to find)
Keil C251 Dev Tools http://www.keil.com/c251/ (ROM USD3k)