It does not cover the PCW16.
Further information is always welcome.
The BIOS routines are called by the BDOS for all screen, disc, and printer operations. Only if b6 is set each time is the PCW in frame flyback. The BIOS interrupt is also slow, and should be disabled for time-critical operations where operations such as keyboard scanning and disc access are not required. The PCW 8256 has 16 banks of 16k each. 512k and expanded machines obviously contain more.