Below "Hidden" RSX commands are having non-ASCII names, so they cannot be used under BASIC by typing |NAME. Instead, they can be used only in machine code, by obtaining the function address via KL_FIND_COMMAND, for details see: [[BIOS Kernel RSX Functions (Resident System Extensions)]]
== Message On/Off ==
chr(81h) MESSAGE_ON_OFF ;in: A=flag(00h=on, >=01h=off) (R,I,C);out:A=old
"V ROM" Vortex VDOS2.0
"Pdos" PARADOS
"Vdos" VARADOS
"ROMDOS " KDS ROMDOS, Siren Software ROMDOS XL, and XL 4.0
"XDDOS ROM" Dobbertin X-DDOS 1.11 and X-DDOS 2.10
"RODOS ROM" Romantic Robot RODOS 2.11, 2.15, 2.19
The names are typically containing "invalid" characters like spaces or lowercase letters, so they can't be accidently accidentally used in BASIC as |NAME.
== Notes ==
* AMSDOS supports only single-sided disks (the FDC supports two sides, but AMSDOS doesn't). All other DOS clones like [[VDOS]], RODOS, ROMDOS, PARADOS, X[[XD-DDOS DOS]] support double-sided disks. However, unknown if/how some/all/which of that clones allow to access the 2nd side via above functions (possibly/best by unused bits in the drive number, or by extending track number to 0..159 for 2x80 tracks)?
* The above chr(8xh) function vectors are usually at ROM7:C033h..C04Dh in AMSDOS, however, clones like VDOS, RODOS, ROMDOS, X-DDOS have the vectors arranged differently, so always use KL_FIND_COMMAND to obtain the function address.
[[Category:Programming]]