Re: need small PAL with SR latch

In article <dOVue.4085$BD2.1932@xxxxxxxxxxxxxxxxxxxx>,
no.spam.for.me@xxxxxxxxxxxx says...
> Hi,
> I need a small prgramable logic device with a couple of SR latches,
> however they all seem to have D types or other type of latch on the macro
> cell with a global clock/set/reset, exept for some of the realy big ones.
>
> Ive looked through all of the ones that Farnell sell, and although I
> could obviously feed back an output to make an SR latch this wouldnt be
> ideal, any one know if there are any like this ?
>
> Only needs a dozen gates or so to do the job, could do with being fast
> as posible and in circuit programable etc.

The Xilinx SpartanXL had RS latch options in the CLBs, but it wasn't
well supported. RS latches tend to cause timing headaches and aren't
recommended. If you insist on RS latches the tools will infer one from
VHDL, though will bitch loudly (at least Synplify would do both).

--
Keith
.

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