Help making ADTrp cable with UART PL2303HX

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Help making ADTrp cable with UART PL2303HX

I recently bought a USB cable to make an interface for my //c plus. It has a Built-in TTL COM PC-PL2303HX Chip, like this:
http://www.sears.com/shc/s/p_10153_12605_SPM7219242928P?ci_src=184425893&ci_sku=SPM7219242928&sid=IDx20131030xMPAPxCPA28

It has a standard USB type A male and TTL 4 pin connector
Black cable-----GND
Green cable-----TXD
White cable-----RXD
Red cable ------VCC

I'm using the Cabling guide from http://adtpro.sourceforge.net/connectionsserial.html but I only connect 3 cables: GND, TXD and RXD. When I try ADTPro it sends garbage and errors. What am I missing? Do I need more connections? I know VCC is power, and I don't need that...
Any help would be greatly appreciated.
Javster.

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Re: Help making ADTrp cable with UART PL2303HX

I am trying to understand why you would spend $6 bucks on it when cheap USB to RS232 adapters are all over fleaBay for about the same (or less) amount of money. Not sure if ADT uses CTS/RTS, but the absence of those handshake lines will make going highspeed tough.

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Re: Help making ADTrp cable with UART PL2303HX

Thanks Dorkbert, I was trying to make a single cable without adapters in between. Those adapters are my last resort.

Not sure if ADT uses CTS/RTS, but the absence of those handshake lines will make going highspeed tough.

I thought the speed was regulated by ADT in the Mac, but after all that's why I'm asking, because I'm ignorant... Smile
Thanks
Javster

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Re: Help making ADTrp cable with UART PL2303HX

The ADT-Pro page doesn't seem to specify whether handshaking is required (skimmed, I may have missed it), but in my experience with similar 8-bit setups, it is.

Not an elegant solution, but if needed you could break into the cable at the USB housing and re-solder the red cable to RI, CTS, etc. depending on what options are available in the host software. Like you say, that +5V is not needed client-side. Besides, hot glue and black tape make you look hax0r leet. Biggrin

I haven't had any bad experiences myself, but others have claimed the PL2303 chip isn't as reliable at higher baud rates as the FT232. There are also driver issues if you're using it with Windows 8.

I am making the assumption that every 8-bit owner also owns a decent soldering iron. Wink

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Re: Help making ADTrp cable with UART PL2303HX

The ADT-Pro page doesn't seem to specify whether handshaking is required (skimmed, I may have missed it), but in my experience with similar 8-bit setups, it is.

Not an elegant solution, but if needed you could break into the cable at the USB housing and re-solder the red cable to RI, CTS, etc. depending on what options are available in the host software. Like you say, that +5V is not needed client-side. Besides, hot glue and black tape make you look hax0r leet. Biggrin

I haven't had any bad experiences myself, but others have claimed the PL2303 chip isn't as reliable at higher baud rates as the FT232. There are also driver issues if you're using it with Windows 8.

I am making the assumption that every 8-bit owner also owns a decent soldering iron. ;)


I was beginning to wonder if the PL2303 was a good choice, and now I'm beginning to believe it wasn't. I was looking for a nice single cable, without big converters in between, but I may have to go back to basics.
Maybe the cable I need is this: http://www.digikey.com/product-detail/en/C232HD-EDHSP-0/768-1112-ND/2767784
But is way too expensive. Let me know if anybody have some ideas.
Cheers
Javster

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Re: Help making ADTrp cable with UART PL2303HX

looking up the stuff some more, that cable you fetched probably works at TTL level designed for Arduino, not RS232.

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Re: Help making ADTrp cable with UART PL2303HX

ADTPro does not require, to the best of my knowledge, RTS/CTS, and David's guidance on the ADTPro page for making a //c cable bypasses them by creating local loops for the handshaking pins. ADTPro's protocol is error-correcting, so I think that it still works pretty well, even at 115,200 (and also it's not dealing with issues like screen scrolling that it can't keep up with).

If the USB end is intended to attach to your Pi, PL2303 should work totally fine. The only adapters I have ever tried with A2CLOUD are based on PL2303, including the $10 TrendNet one I linked on the A2CLOUD web site. I also bought a different PL2303 based adapter on eBay with quite a long cable (I think it was "Best Connectivity"); you could chop off the DB-9 end if and put on a DIN-5 or miniDIN-8 if you didn't want to attach it to another cable.

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Re: Help making ADTrp cable with UART PL2303HX

ADTPro does not require, to the best of my knowledge, RTS/CTS, and David's guidance on the ADTPro page for making a //c cable bypasses them by creating local loops for the handshaking pins. ADTPro's protocol is error-correcting, so I think that it still works pretty well, even at 115,200 (and also it's not dealing with issues like screen scrolling that it can't keep up with).

If the USB end is intended to attach to your Pi, PL2303 should work totally fine. The only adapters I have ever tried with A2CLOUD are based on PL2303, including the $10 TrendNet one I linked on the A2CLOUD web site. I also bought a different PL2303 based adapter on eBay with quite a long cable (I think it was "Best Connectivity"); you could chop off the DB-9 end if and put on a DIN-5 or miniDIN-8 if you didn't want to attach it to another cable.

Thanks Ivan, after reading your comment I tried again, with two different cables. I test by running ADTPro, Configure Serial, and send Speediboot to the //c plus. I got 4 Serial Devices:
/dev/tty/usbserial
/dev/cu/usbserial
/dev/tty-NOZAP-PL2303-00002014
/dev/cu-NOZAP-PL2303-00002014

I tried all with all possible combinations: 19200 and 115200, change bootstraping pacing and speed, all with no different results, just get a bunch of garbage on the //c and "?SYNTAX ERROR" with beeps.

I'm beginning to think it does need RTS/CTS, but that's part of why I am asking... Biggrin
Anyway, thanks for sharing your knowledge, and let me know of any ideas.
Javster

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