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Hardware muldiplier/divider for PIC16C57 on FPGA, but how do I program it?

Started by Kelv...@ SG March 25, 2004
Hi, there:

I am doing some exercise with a PIC15C57 core on FPGA. Now I am adding a
multiplier to
address 7C~7F...Basically in assembly I will write two variables to 7C & 7D,
then fetch the
result from 7E & 7F...Similar idea to a divider...Will such a crazy idea
find application in the
real world? Plus...I can add stuff like UART, DDS, etc...

Kelvin




> >I am doing some exercise with a PIC15C57 core on FPGA. Now I am adding a >multiplier to >address 7C~7F...Basically in assembly I will write two variables to 7C & 7D, >then fetch the >result from 7E & 7F...Similar idea to a divider...Will such a crazy idea >find application in the >real world? Plus...I can add stuff like UART, DDS, etc...
Highly unlikely, to make some thing like this successful it needs to be unique or faster or cheaper.
Kelvin @ SG schrieb:
> > I am doing some exercise with a PIC15C57 core on FPGA. Now I am adding a > multiplier to > address 7C~7F...Basically in assembly I will write two variables to 7C & 7D, > then fetch the > result from 7E & 7F...Similar idea to a divider...Will such a crazy idea > find application in the > real world? Plus...I can add stuff like UART, DDS, etc... >
Hello, if I would need a hardware multiplier and divider on a processor, I would select a processor with this feature. But DDS on a FPGA may be useful, if the commercially available DDS chips would not fit for the application. Bye
Kelvin @ SG <kelvin8157@hotmail.com> wrote in message
news:40629dff@news.starhub.net.sg...
> Hi, there: > > I am doing some exercise with a PIC15C57 core on FPGA. Now I am adding a > multiplier to > address 7C~7F...Basically in assembly I will write two variables to 7C &
7D,
> then fetch the > result from 7E & 7F...Similar idea to a divider...Will such a crazy idea > find application in the > real world? Plus...I can add stuff like UART, DDS, etc... > > Kelvin
The registers at 70 to 7F are a valuable resource on many 14 bit PICs. They provide an area of RAM that is bank independent. If you intend to entend your 57 to have multiple RAM banks you may want to put your multiplier ports somewhere else. Regards Sergio Masci http://www.xcprod.com/titan/XCSB - optimising structured PIC BASIC compiler
well...it's fun to learn how to design a microcontroller and peripherals...

Though it may not be so useful, but will my 8bit PIC become useful if
I expand the data/address bus to 32-bit?

Will it become useful if I design make the program address to 20-bits...
thus make it run 1MB programs? What will MPLAB do when the C program
is longer than 2048Bytes?

Best Regards,
Kelvin







Kelvin @ SG <kelvin8157@hotmail.com> wrote in message
news:40629dff@news.starhub.net.sg...
> Hi, there: > > I am doing some exercise with a PIC15C57 core on FPGA. Now I am adding a > multiplier to > address 7C~7F...Basically in assembly I will write two variables to 7C &
7D,
> then fetch the > result from 7E & 7F...Similar idea to a divider...Will such a crazy idea > find application in the > real world? Plus...I can add stuff like UART, DDS, etc... > > Kelvin > > > >