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CPLD Attributes Used in Schematics

webpack00090000.gif BUFG=CLK|OE|SR on an IBUF symbol or its input net (the pad net).
(Assigns global buffers to internal nets or to input pins in a top-level design. CLK=Global Clock, OE=Global Output Enable, SR=Global Set/Reset)

webpack00090000.gif COLLAPSE on a logic symbol or its output net.
(Forces a logic mode to be collapsed into all of its fanouts.)

webpack00090000.gif FAST | SLOW on an OBUF, OBUFE or OBUFT type symbol or its output net (the pad net).
(Selects output slew rate for output pins in top-level design.)

webpack00090000.gif INIT=R|S on a flip-flop or other registered macro symbol or its output net.
(Defines initial state of registers.)

webpack00090000.gif KEEP on a logic symbol or its output net.
(Preserves internal nodes during design implementation.)

webpack00090000.gif LOC=Ppin_number|BGA_pin_name [eg. LOC=P23, LOC=AC17] on any pad or pad net.
(Assigns a device pin number to an input or output pad of the design.)

webpack00090000.gif LOC=FBnn [eg. LOC=FB3] on a logic symbol or its output net, or on an output pad or the pad's net.
(Assigns an internal Function Block number to logic driving an internal node or device output; typically used only to control XC9500 local feedback routing.)

webpack00090000.gif NOREDUCE on a logic symbol or its output net.
(Preserves redundant logic terms during design implementation.)

webpack00090000.gif PROHIBIT on unused device pins allows you to reserve the pins for later use, or simply to prevent them from being used at all.

webpack00090000.gif PWR_MODE=LOW|STD on a logic symbol or its output net.
(Selects macrocell power mode for nodes or outputs in CPLD designs.)

webpack00090000.gif REG=CE|TFF on a FDCE or FDPE primitive or its output net.
(REG=CE forces the CE pin to be implemented using the clock enable product term of the XC9500XL or XC9500XV macrocell. REG=CE attributes are ignored for XC9500 macrocells. REG=TFF indicates that the register is to be implemented with a T-type-flip-flop. REG=TFF on a D-type-flip-flop will cause the D-input expression to be converted to a T-input expression.)

webpack00090000.gif TNM=group_name [eg. TNM=MY_GROUP1] on any pad, flip-flop symbol or any net.
(Tags signals with a Timing-group Name to be used in a Timespec.)

webpack00090000.gif TSnn=FROM:source_group:TO:dest_group:delay
[eg. TS02=FROM:PADS(IBUS*):TO:MY_GROUP1:16] on a TIMESPEC symbol.
(Defines a point-to-point timing constraint.)

webpack00090000.gif TSnn=PERIOD:clock_group:delay [eg. TS10=PERIOD:CLK1_GRP:12] on a TIMESPEC symbol.
(Defines a clock period timing constraint.)