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Vacuum 6
11-08-2004, 11:27 AM
When using a scan tool via the ALDL plug why isn’t information displayed in real-time? What is the bottle neck?
Eric Marshall
11-08-2004, 02:16 PM
The ECM will only send the data at a certain rate. The program is written that way, and unfortunately it's in the ROM, which we can't change. (Actually, the ROM can be changed, but the ECM has to be modified.)
Vacuum 6
11-08-2004, 03:03 PM
The ECM will only send the data at a certain rate. The program is written that way, and unfortunately it's in the ROM, which we can't change. (Actually, the ROM can be changed, but the ECM has to be modified.)

Has anyone tried changing the ECM to increase the data rate? Has anyone successfully done it?
Vacuum 6
11-10-2004, 11:58 AM
Eric or anyone else...is there a way to hook up the OTC or Scan Master other than the ALDL plug? Hook up directly to the ECM bus like Direct Scan?
Eric Marshall
11-10-2004, 12:22 PM
Directscan is the only commercially available device that will hook up to the factory service port. Scanmaster and OTC, etc. are expecting a serial datastream (1-wire), so those won't be compatible with the service port. The service port has direct access to all the address lines, so you get real time data there.
As far as the ALDL stuff, we're pretty much stuck with the slower speed there.