Force Computers SYS68K/CPU-40, User Manual

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SECTION 9 APPLICATION COMMAND INTERFACE PROGRAMMING GUIDE
2-19
_remnant:
This data area may be used by the device driver for additional parameters. For further information
please refer to the detailed description of the device driver.
When the WRITE command has been carried out by the device driver the status of the completion
of the command is returned through the same Command Control Buffer used to issue the
command. The structure of the corresponding Command Control Buffer is described below.
typedef struct _ccb_write_status
{
unsigned long _access_control_flags;
long ( *ME_system_call ) ( );
CCB *ccb_link;
long last_command;
unsigned long _reserved[ 7 ];
long status;
unsigned char *buffer;
unsigned long count;
unsigned long block_number;
unsigned long write_mode;
unsigned long _remnant[ 48 ];
} CCB_WRITE_STATUS;
_access_control_flags:
The BUSY and the PROCESS semaphore are both cleared to signal the completion of the
command. All other semaphores are unaffected.
status:
The status reports the state of the completion of the command and either indicates the successful
completion or the termination of the command due to the recognition of an error. In the former case
a zero is returned; in the latter case a negative value is returned. The following error codes are
returned by the Application Command Interface directly.
ACI_OK:
Indicates the successful termination of the command
ACI_E_ILLEGAL_COMMAND:
An illegal command code has been specified.