Memory used by the IO structure will be returned back to AMOS Professional and the message port is released for subsequent use. If the channel number is omitted, all active devices are closed simultaneously, otherwise the single specified device is closed down. Note that if a specified channel is not already open, no error will be reported.
DEV DO
instruction: call a command using DoI0
Dev Do channel number,command number
The DEV DO instruction executes a DoIO operation via the specified channel. Obviously the correct internal structure parameters must be set using a STRUC command, before this operation is called. The specified channel number refers to a previously opened device channel. The command number holds the number of the IO command you wish to Do. This command may be entered directly by name, using the EQU function explained earlier. You are warned to take great care when using this instruction!
DEV SEND
instruction: call a command using SendIO
Dev Send channel number,command
This calls the SendIO command from Exec, and runs your operation using the Amiga's multi- tasking system. The new process will run invisibly in the background, and your AMOS Professional program will continue from the next instruction immediately.
DEV CHECK
function: check status of a device with a CheckIO
value=Dev Check(channel number)
Use this function to perform a CheckIO on the specified channel. The resulting value is passed back to AMOS Professional.
DEV ABORT
instruction: abort an IO operation
Dev Abort channel number
This instruction executes an AbortIO and a WaitIO command, clearing all pending action from the specified device channel. It can be used to exit directly from a multi-tasking operation, without waiting for it to complete.
DEV BASE
function: get base address of an IO structure
address=Dev Base(channel number)
This function returns the base address of the IO structure assigned to the current device. The structure can now be manipulated directly, using the STRUC commands, as required.