AR# 1349

XABEL: How to assign preload value to registers in an EPLD


From my ABEL file, how can I control the preload value of macrocell registers
during device powerup?

*NOTE*: This Solution applies to EPLDs only. For information on assigning
preload values to FPGAs, see Solution #1350



In M1, use:
XILINX PROPERTY 'INIT=S|R signal_name...';

(xepld_property syntax is obsolete in M1.)


To assign a preload value to a register, use the following
XEPLD property statement in the DECLARATIONS section of the
ABEL file.

xepld property 'EQUATION <reg_name>.PRLD = VCC|GND';

For example, to preload a register to 0 at powerup:

xepld property 'EQUATION <reg_name>.PRLD = GND';

OR, to preload a register to 1 at powerup:

xepld property 'EQUATION <reg_name>.PRLD = VCC';

Where <reg_name> is a register previously declared in the
AR# 1349
日期 03/29/2000
状态 Archive
Type 综合文章