InvisiBill
Active member
Looking at ALDL to serial schematics... Is there a +12V pin on the ALDL, or do you need to use a cigarette lighter adapter (or equivalent) for that? Hopefully I'll have some DM files pretty soon...
ALDL +12V ?
- Thread starter InvisiBill
- Start date
93 TY 2185
Donating Member
No 12v at the ALDL connector. You will need to use the cigarette lighter or some other 12v source. Are you making your own cable? You are converting TTL (ALDL) to serial (LAPTOP) . Maxim makes a great chip for this MAX233 this part needs very little in the way of external components. Call me if you want help with this I've built a few of these and I have the parts.
734-741-6280
Wade
734-741-6280
Wade
InvisiBill
Active member
Thanks. I found a schematic for a two transistor circuit at Techedge. The transistors were $2 each from work, we had the diode laying around, and I picked up the DB9 and resistors from Rackety Shack for another $2.50 this weekend. They mention that it's a "sneak preview" of the circuit, which they'll describe later... If anyone knows that it won't work (i.e. only a partial circuit, something needs to be changed, whatever), you can go ahead and let me know now, before I build it.
Depends on who you ask. I borrowed a cable from a local guy and his had the 12 Volt source coming from the cigarette lighter. The cable I ordered from Andrew did not. He must have been getting power from the ALDL or something crazy like that. I do like the cleanliness of Andrew's cable - but the one I borrowed seemed to connect much better. Guess it is a trade off.
Originally, all of Andrew's cables came with the plug for the cigarette lighter. However, it turned out that plugging it in wasn't always necessary because (usually) the laptop supplied enough power to run the conversion circuit. I guess he just decided to drop the plug and always let the laptop provide power.GM TURBO said:
BTW, no power ever comes from the ALDL plug, it's just not available.
InvisiBill
Active member
Well, got it put together. It all fits right inside the DB9 shell, which makes it nice and compact. Tonight I can see if it actually works...
Falco
Donating Member
Bill,
Do you have the layout and the required components? I'd appreciate if you could send me. falco@attglobal.net
TIA,
Do you have the layout and the required components? I'd appreciate if you could send me. falco@attglobal.net
TIA,
InvisiBill
Active member
What do you mean by layout? I just used the schematic above, with two NPN transistors (9507 or something?) and three 10k 1/4watt resistors. I just soldered it all together free-air, and got it to fit inside the DB9 shell.
InvisiBill
Active member
Added a $1.29 cigarette lighter plug, and it works great with both Freescan and DataMaster.