Schematic of a GM ALDL -> PC converter

[SRavet at bangate.compaq.com]

Darrell Norquay <dnorquay at iul-ccs.com> Wrote:
| 
| At 10:16 AM 11/26/96 CST, you wrote:
| 
| Markus Strobl <eusmsrt at exu.ericsson.se> Wrote:
|  
| >| Does anyone have a schematic of a GM late model ALDL to 
| >| PC converter? By late model I mean the late 80s/90s
| >| 8192 baud ALDL.
|  
| Steve Ravet wrote:
| 
| >The Diacom software uses the parallel port to watch the serial data pin 
of 
| >the ALDL.  It implements a UART in software.  It does have timing 
problems, 
| 
| Seems to me these guys are going about this all wrong.  The 68HC11 has a 
mode 
| where it's serial port talks at 8192 baud.  I'm pretty sure GM EMU's are 
| 68HC11 based, thus the oddball baud rate.  In the words of the prophets, 
you
| need a lawyer to talk to a lawyer.  It would be a simple matter to setup 
a 
| small 'HC11 module to either log the data, display it, or both.  You 
could
| add a second UART to the 'HC11 and just use it as a buffered baud rate 
| converter to talk to a laptop.

Could do that also.  The thing is that there are two baud rates available, 
8192 and 160.  As I wrote in another post, the 160 data stream will never 
hook directly to any serial port, because every bit has it's own start bit. 
 Using the parallel port makes sense for diacom, because then it's an "all 
software" solution that works for both data rates.

--steve

| 
| regards
| dn
| dnorquay at iul-ccs.com
| 
| 


Steve Ravet
sravet at bangate.compaq.com
Baby you're a genius when it comes to cooking up some chili sauce...