Re: [E3-hacking] Cheap PL2303 cable @ Ebuyer
On 7 Jul 2005, at 15:26, Rahim Nathwani wrote:
http://www.ebuyer.com/customer/products/index.html?product_uid=51518
It's USB at one end, and Nokia pop-port at the other. It doesn't play nicely with current versions of Nokia PC Suite, but might be a good alternative to a home-made MAX232 (which would probably work out around the same price).
That looks like a bargain! Also - the picture's a little small but that looks very much like the T610 cable I have, so hopefully same manufacturer. (There's a little rectangular 'pod' with a PCB inside.) If it is the same as the one I have then it has the advantage that it's not sealed into a resin glob, but there's the disadvantage that it needs a mod for 5V which requires soldering a tiny leg on the PL2303. -Matt
On Thursday 07 July 2005 15:35, Matt Evans wrote: [...]
That looks like a bargain! Also - the picture's a little small but that looks very much like the T610 cable I have, so hopefully same manufacturer. (There's a little rectangular 'pod' with a PCB inside.) If it is the same as the one I have then it has the advantage that it's not sealed into a resin glob, but there's the disadvantage that it needs a mod for 5V which requires soldering a tiny leg on the PL2303.
Well, I now have one. I should be getting scans of it reasonably soon. The phone end of the cable is marked N-5100; oddly, that seems to be the only mention of what kind of phone it's for... The plastic box the PCB is inside has a space for a switch, marked L and R, but there is no switch there and there are no pads on the PCB for installation of one. I suspect someone's been saving money. Here's the PL2303 data sheet: http://tech.prolific.com.tw/visitor/fcabdl.asp?fid=33962507 I can't tell whether my device is set up for 5V or 3.3V; I'll just have to plug it in and measure it. Is it known that the E2 *doesn't* work with 3.3V? And what's the modification I need to do? -- +- David Given --McQ-+ "`Aplysia californica' is your taxonomic | dg@cowlark.com | nomenclature. | (dg@tao-group.com) | A slug, by any other name, is still a slug by +- www.cowlark.com --+ nature." --- drushel on a.f.c
Howdy David, On 13 Jul 2005, at 12:56, David Given wrote:
The plastic box the PCB is inside has a space for a switch, marked L and R, but there is no switch there and there are no pads on the PCB for installation of one. I suspect someone's been saving money.
Sounds like mine - box-wise - though the PCB is different.
I can't tell whether my device is set up for 5V or 3.3V; I'll just have to plug it in and measure it. Is it known that the E2 *doesn't* work with 3.3V? And what's the modification I need to do?
Yeah that's probably the best way - see if TxD is 5V or 3.3V. The real issue isn't whether the E2 will talk at 3.3V (IIRC it /does/ work at this voltage) but whether you'll zap the input on the PL2303 by driving 5V into a 3.3V input. *reads datasheet, which always helps* OK, no, you should be alright :-) It says the inputs are always 5V-tolerant. So, it will probably Just Work - cross the voltage-too-low bridge if you come to it. (Modify the cable to run I/O at 5V rather than 3.3V if necessary.) Good luck! -Matt
On Wednesday 13 July 2005 14:07, Matt Evans wrote: [...]
:-) It says the inputs are always 5V-tolerant. So, it will probably Just Work - cross the voltage-too-low bridge if you come to it. (Modify the cable to run I/O at 5V rather than 3.3V if necessary.)
Actually, it never occurred to me that it might be in danger --- the idea of a USB slave chipset that can't cope with 5V inputs is a bit bizarre, given that USB is all 5V! (In fact, I'm a little bemused about why the PL2303 is powered off 3.3V.) Looking closely at the PCB it actually looks like quite a nice little thing; there are pads for all the output signals, so if you want DTR or RTS they're available, and there's a whole bunch of diagnostic pads of unknown purpose. There's also a 8-pin IC blank and a six-pin jumper blank. I suspect this is for the PL2303's configuration EEPROM. There's definite hacking possibilities here. -- +- David Given --McQ-+ "There are two major products that come out of | dg@cowlark.com | Berkeley: LSD and Unix. We don't believe this to be | (dg@tao-group.com) | a coincidence." --- Jeremy S. Anderson +- www.cowlark.com --+
On Wednesday 13 July 2005 12:56, David Given wrote: [...]
Well, I now have one. I should be getting scans of it reasonably soon.
Scans available: http://www.cowlark.com/amstrad.html I'll stick a plug on it this weekend and see if it works. -- +- David Given --McQ-+ "Preacher, don't the Bible have some pretty | dg@cowlark.com | specific things to say about killing?" "Quite | (dg@tao-group.com) | specific. It is, however, somewhat fuzzier on the +- www.cowlark.com --+ subject of kneecaps." --- Firefly, _War Stories_
David Given <dg@cowlark.com> writes:
On Wednesday 13 July 2005 12:56, David Given wrote: [...]
Well, I now have one. I should be getting scans of it reasonably soon.
Scans available:
From the pics it looks like it is built to take a 9-pin D connector - even the mechanical mounting holes are there. That would make it more versaitile I think - a lead with the appropriate 9-pin D and whatever connectors can then be used for each relevant project.
That assumes of course that connecting a 9-pin D pulls the things out on the right pins .... Pete
On 14 Jul 2005, at 15:20, Peter Riocreux wrote:
David Given <dg@cowlark.com> writes:
On Wednesday 13 July 2005 12:56, David Given wrote: [...]
Well, I now have one. I should be getting scans of it reasonably soon.
Scans available:
From the pics it looks like it is built to take a 9-pin D connector - even the mechanical mounting holes are there. That would make it more versaitile I think - a lead with the appropriate 9-pin D and whatever connectors can then be used for each relevant project.
It'd be a little tempting (for those sleepy late-night engineers) to plug a real RS232 plug into that DB9 though, which'll probably zap the PL2303 ;) I just looked at the scans - that board is the same as mine - first picture, look at the pads along the bottom. That's where my switch is. I believe there's space for a SMT MAX232-alike on there, and inductors - i.e. the board is designed for a full RS232-USB serial dongle. -Matt
On 14 Jul 2005, at 15:45, Matt Evans wrote:
It'd be a little tempting (for those sleepy late-night engineers) to plug a real RS232 plug into that DB9 though, which'll probably zap the PL2303 ;)
Use a 9-pin mini-DIN, Macintosh-style, then? Also Psion Series 3 style and newer Sun style, I recall. -J.
participants (4)
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David Given -
Jasmine Strong -
Matt Evans -
Peter Riocreux