Extensible Firmware Interface Specification
214 12/12/00 Version 1.02
SetControl Set the control bits on a serial device. These include Request to
Send and Data Terminal Ready.
GetControl Read the status of the control bits on a serial device. These include
Clear to Send, Data Set Ready, Ring Indicator, and Carrier Detect.
Write Send a buffer of characters to a serial device.
Read Receive a buffer of characters from a serial device.
Mode Pointer to SERIAL_IO_MODE data. Type SERIAL_IO_MODE is
defined in “Related Definitions”.
Related Definitions
//*******************************************************
// SERIAL_IO_MODE
//*******************************************************
typedef struct {
UINT32 ControlMask;
// current Attributes
UINT32 Timeout;
UINT64 BaudRate;
UINT32 ReceiveFifoDepth;
UINT32 DataBits;
UINT32 Parity;
UINT32 StopBits;
} SERIAL_IO_MODE;
The data values in the SERIAL_IO_MODE are read-only and are updated by the code that
produces the SERIAL_IO_INTERFACE protocol functions:
ControlMask A mask of the Control bits that the device supports. The device must
always support the Input Buffer Empty control bit.
Timeout If applicable, the number of microseconds to wait before timing out a
Read or Write operation.
BaudRate If applicable, the current baud rate setting of the device; otherwise,
baud rate has the value of zero to indicate that device runs at the
device’s designed speed.
ReceiveFifoDepth The number of characters the device will buffer on input.
DataBits The number of data bits in each character.