[Opendispense] Questions - new memory map

Bernard Blackham bernard@blackham.com.au
Wed Aug 13 15:49:44 2003


On Mon, Aug 11, 2003 at 03:10:50PM +0800, Harry McNally wrote:
> - Terminate the four wire wrap pitails on signals needed for read and
>   write and full addressing (A15) onto the PCB.

So the questions remain, which 4 lines do we want to run up? Almost
necessarily - A15, R/W, Enable. This leaves one more to choose from:

 - Interrupt line, possibly the most useful - but could use polling
   instead.

 - Clock - running this line up here saves us a crystal on the
   daughterboard for the UART. Though, we can probably afford
   another crystal on the board.

 - Reset - to reset the state of the UART with the CPU. needed?

I'm leaning towards the interrupt line because it appears to make
the serial comms that much more reliable. Any strong reasons for any
of the others?

Regards,

Bernard.

-- 
 Bernard Blackham 
 bernard at blackham dot com dot au