[sdiy] Another new hard to find part....

[James Patchell]

The reason I mentioned the XC9536 is that it is possible to in circuit 
program it.  There are (supposedly) in circuit programmable 22V10s as well, 
but I am not sure how they accomplish this.  The 9536 has dedicated 
pins.  If getting certain SSI TTL logic functions begins to get 
problematic...I suppose I will have to cave...I have to admit, writing 
logic functions in Verilog is a lot simpler than doing logic design the old 
fashioned way...

At 05:26 PM 7/5/2004 +0200, Ingo Debus wrote:

>Am Montag, 05.07.04 um 06:59 Uhr schrieb James Patchell:
>
>>Recreating the 74HC283 with "discrete" circuitry, while an interesting 
>>exercise, would be problematic...i.e...way too many parts.  I could 
>>recreate the functionality with a CPLD, like say a Xilinx XC9536
>
>The 74283 could probably be recreated with a "simple" PLD like the 22V10 
>too. I haven't investigated if it's really possible, perhaps it's 
>necessary to generate the "internal carry" with an extra product term, so 
>the PLD would probably be slower than the original. Of course it's not 
>pin-compatible, since the 74283 has 16 pins.
>Isn't there even a "in-system-programmable" version of the 22V10 available 
>that requires no programming hardware?
>
>Ingo

         -Jim
***************************************************************
http://www.oldcrows.net/~patchell

***************************************************************