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MagTek Communications Protocol, Driver Reference Manual
52
MCPBUS Structure
The MCPBUS structure represents a common structure (bus) used to pass arguments to the MCP
API functions. Not all members of this structure are used for every function; refer to each
function description below to determine how the members are used.
typedef struct _MCPBUS
{
DWORD dwOperAttribute ; // operation attribute
DWORD dwApplicationID ; // application ID
DWORD dwCommandID ; // command ID
DWORD dwResultCode ; // command/notification result code
LPSTR lpszPropertyName ; // pointer to property name
DWORD dwPropertyID ; // property ID
DWORD dwPropertyType ; // property type
LPVOID lpInBuffer ; // pointer to input buffer
DWORD dwInBufferLen ; // length of data in input buffer
LPVOID lpOutBuffer ; // pointer to output buffer
DWORD dwOutBufferSize ; // output buffer size
DWORD dwResponseLen ; // length of response in output buffer
DWORD dwTimeout ; // notification timeout value
DWORD dwContext ; // device enumeration context
} MCPBUS, *PMCPBUS;
Members
dwOperAttribute
Operation Attribute. Some MCP API functions require this member to be set prior to invoking
the function to distinguish how the operation is processed. The following table defines the
attributes and for which functions they apply.
Function Code Meaning
MCP_ATTR_NONE Do not discard any queued notifications
before responding.
McpWait
MCP_ATTR_WAIT_NEW Discard any notifications that may have
been queued before returning a response.
MCP_ATTR_NONE MCP Device specific property McpGet, McpSet
MCP_ATTR_PROP_DRIV
ER
MCP Driver Device instance specific
property