Specifications

254 www.xilinx.com Embedded System Tools Guide (EDK 6.2i)
1-800-255-7778 UG111 (v1.4) January 30, 2004
Chapter 16: Microprocessor Peripheral Description (MPD)
R
The level is dependent on the speed of the interface that the IP controls. For example, a
UART runs at default 19200 baud, which gives a byte-rate of around 2000 bytes/s. An
ethernet 100 runs at 100 MHz, which gives a byte-rate of 12 000 000 bytes/s. Therefore,
UART is LOW and ethernet is HIGH.
CANBus runs at 1 MHz and gives a byte-rate of 120 000 bytes/s which would be
MEDIUM. It is also dependent if the IP has FIFO or not. It is a judgment that the designer
has to make.
IOB_STATE
The IOB_STATE keyword identifies ports that instantiate or infer IOB primitives.
Format
PORT DDR_Addr = “”, DIR=OUT, VEC=[0:C_DDR_AWIDTH-1], IOB_STATE=REG
The values are BUF, INFER, or REG. The default is INFER.
When a port requires an IOB primitive (IOB_STATE=INFER), PlatGen instantiates an IOB
buffer. When a port has an IOB buffer (IOB_STATE=BUF) or IOB register
(IOB_STATE=REG), PlatGen does not instantiate an IOB primitive.
IO_IF
IO interface association name.
Format
PARAMETER C_HAS_EXTERNAL_RCLK=0, IO_IF=uart_0, IO_IS=has_ext_rclk
IO_IS
A unique identifier name.
Format
PARAMETER C_FAMILY=virtex, IO_IF=uart_0, IO_IS=C_FAMILY
INITIALVAL
The signal driver value on unconnected input signals is specified by the INITIALVAL
keyword.
Format
PORT mysignal = “”, DIR=INPUT, INITIALVAL=init_value
Where the init_value is either VCC or GND. If there is no specification, then GND is the
default value.
LEVEL
The level sensitivity of an interrupt signal is specified by the LEVEL keyword. Its use is
deprecated. Please use the SENSITIVITY keyword.
Format
PORT interrupt = “”, DIR=O, LEVEL=level_value, SIGIS=INTERRUPT
Where the level_value is either HIGH or LOW.