[Coco] DriveWire for TC-9/SWTPC/M68MM17

[Steve]

As Aaron pointed out that the driver section of the client can be 
re-written for new timing.  The point I was trying to make that it's 
easier to to use a hardware communications device than writing a driver 
that uses 100% of the CPU while transferring the data.  (Not good for a 
multitasking and multiuser OS like OS-9.)

As for the timing on the server side, your going to want to re-write the 
code anyway for these new systems.  After all, Aaron tuned the DriveWire 
for the speed of the CoCo.  You will need to do the same for these other 
computers and the servers they use. (Not an easy task.)

Steve


On 12/29/2013 6:54 PM, Joel Ewy wrote:
> Steve, this was my understanding -- that a UART like the 6850 or 6551 
> couldn't keep up with the Bit-banger if used in the wayDriveWire 
> does.  And my purpose is not to transfer data to and from these 
> computers with zmodem or some such, but actually to hook these other 
> OS-9 computers up to a DriveWire 4 server.  For me it would be much 
> simpler to build a little adapter to use the existing DriveWire code 
> off the rack than to try to re-jigger somebody's fine tuning, or 
> re-implement a DriveWire client over a UART.
>
> The way it looks at the moment, the TC-9 may be able to run the stock 
> CoCo DW client, assuming FHL didn't do something untoward with all the 
> PIA pins, which is a distinct possibility.  The SWTPC and Motorola 
> MM17 have 6821s in the free and clear, but are clocked at 1 or 2 MHz.  
> So to get them to work, they would have to be "clock chipped" or the 
> DW routines will need to be tweaked for a different clock rate.
>
> JCE
>