Specifications

Operating System Routines
EXE$SETCHAR, EXE$SETMODE
EXE$SETCHAR, EXE$SETMODE
Write device-specific status and control information into the device’s UCB and
complete the I/O request (EXE$SETCHAR); or write the information into the IRP
and deliver the IRP to the driver’s start-I/O routine (EXE$SETMODE).
Module
SYSQIOFDT
Input
Location Contents
R3 Address of IRP
R4 Address of current PCB
R5 Address of UCB
R6 Address of CCB
R7 Bit number of the I/O function code
R8 Address of FDT entry for this routine
00(AP) Address of location containing device characteristics
quadword (p1)
UCB$B_DEVCLASS Device class
Output
Location Contents
R0 SS$_NORMAL, SS$_ACCVIO, or SS$_ILLIOFUNC
UCB$B_DEVCLASS Byte 0 of quadword (EXE$SETCHAR,
IO$_SETCHAR function only)
UCB$B_DEVTYPE Byte 1 of quadword (EXE$SETCHAR,
IO$_SETCHAR function only)
UCB$W_DEVBUFSIZ Bytes 2 and 3 of quadword (EXE$SETCHAR)
UCB$Q_DEVDEPEND Bytes 4 through 7 of quadword (EXE$SETCHAR)
IRP$L_MEDIA First longword of device characteristics
(EXE$SETMODE)
IRP$L_MEDIA+4 Second longword of device characteristics
(EXE$SETMODE)
Synchronization
EXE$SETCHAR or EXE$SETMODE is called as a driver FDT routine at IPL$_
ASTDEL.
3–57