SynthModules

grantrichter2001 (08:37 AM 4/8/2004) wrote:

 >Continuing my thinking out loud on the MIDI input.
 >
 >How would one handle a buffer in this BASIC?
 >
 >It does not support STR$ command or some of the other 16K
 >BASIC features for string handling.
 >
 >It seems you would have to use an array variable and brute force
 >move all bytes for a first in last out string.
 >
 >Any suggestions?

This is where I was going with my questioning about how the PSIM program 
memory is organized... I wanted to get some background before I started 
babbling about the issues of BASIC as an ISR for a comm buffer.

Trying to do a FIFO buffer in a minimal BASIC will be most interesting. A 
bunch of questions...

- I trust that there's ISR handling of some sort in the language 
implementation?

- Is the PIC mapped such that you can control it? Either port or memory?

- Can the UART be setup to be memory mapped so that it dumps a byte 
straight to memory, or is it port mapped?

- Have you done any timings on reading from a port, moving a byte/word of 
memory?

- Does this BASIC allow for PEEK and POKE? Can you get the address of a 
variable? The thought behind this is that PEEK/POKE would be faster than:

   CommBuffer[CommIndex] = $UARTIn
   CommIndex = CommIndex + 1;


Just some random questions...

Mark