Christain:

Some things to think about.

1) It is very easy to make an SPI controller inside of a small 32 or 64 macrocell CPLD.

2) A very effective way to make an SPI controller is to use a small package type of microcontroller that has onboard code memory which is programmed with firmware to make it "smart peripheral" chip.

3) If you have the appropriate clocking signal available (possibly from a timer output on your microcontroller) it is possible to build a SPI controller from discrete HC type logic chips using one or two shift registers and a counter IC.

and finally.......I have to guess that you want an outboard chip solution for an SPI controller either because you ran out of I/O pins or you are finding software bit banging too slow. If either is the case you should consider......

4) Some of the 8051 type microcontrollers have onboard SPI controllers (look also for an interface called SM Bus controller..its same thing). You should consider swapping out your existing microcontroller for one of these newer types.

Michael Karas