Using JP1.x Interface with a USB-to-Serial Adapter

[Tommy Tyler]

A bit off topic, but will the JP1 serial cable work with the adapter as well? I know there is a USB version as well, but with parts I have around, serial version would be simpler to make, and I'd try it if there's a possibility.

Sorry, the JP1 cable will not work with a serial to USB adapter because, rather than using true RS232 serial communications as a JP1.x cable does, JP1 uses a couple of control lines in "bit bang" mode to clock data directly to/from the EEPROM, and the USB port wouldn't have a clue what the signals are.

Thanks for letting us know about your success with the USB adapter.

Tommy

[tommysingh]

Guys...

please help - im no technical expert in the area...

i've got a brother card reader that is meant to connect via serial...

bought this hugepine usb to rs232 cable off ebay... i have xp service pack 1 (i think)... what the hell is wrong with it because it wont work... the software i use says nothing is connected... i tried it on win2000 and it works fine...

any ideas?

(another Tommy surely will confuse the matter further)

[prelude]

can you identify the chipset? is it a PL2303?

[cywelchjr]

Here is something I have found that I have not noticed anywhere else. I can only use the serial cable with my USB to serial adapter if I plug in the adapter before I boot the computer. If I plug it in aftwards, it can't open the port, even though other programs seem to be able to. As long as I plug it in before I boot, or I restart after plugging it in, then it work fine (at least with the JP1.2 cable I bought from DIYGadgets, the 1.x cable that I got to modify I appear to have damaged while modifying it, and just haven't gotten around to having the time to figure it out yet (it was frankly cheaper for me to just buy a good one that didn't need modded)).

Hope this helps,

Cy
1 9910, 3 Millenium 4's, 3 Comcast 1067A's and one Visio OEM 1.2 remote.

[cursedgriffin]

i was having the problem where IR7beta3 kept saying "failed to open JP1.2 interface" when i was using my jp1.2 serial cable, so i went to radioshack and bought a usb->serial adapter, and after installing drivers i still get the failed to open jp1.2 interface eventhough the tester detects my jp1.2 remote....any advice?

[prelude]

I bought 3 different brands of USB to Serial adapter, none of them work. One I believe has PL2303 chip, but it is a custom firmware made by Alcor Micro (PID = 9720). Here is the tester.exe result:

Code: Select all

D:\jp12.test>debugtester.exe COM6
tester version 0.01
jp12io.dll version 0.01
Parsing command list file tester.dat
Openning COM6
DCB paramaters:
  DCBlength=28
  BaudRate=38400
  fBinary=1
  fParity=0
  fOutxCtsFlow=0
  fOutxDsrFlow=0
  fDtrControl=1
  fDsrSensitivity=0
  fTXContinueOnXoff=0
  fOutX=0
  fInX=0
  fErrorChar=0
  fNull=0
  fRtsControl=1
  fAbortOnError=0
  fDummy2=0
  wReserved=0
  XonLim=0
  XoffLim=0
  ByteSize=8
  Parity=0
  StopBits=2
  XonChar=17
  XoffChar=19
  ErrorChar=0
  EofChar=0
  EvtChar=0
  wReserved1=0
Unable to connect

[jherrick]

I just tested the jp1.x cables that I build with a Parallax USB to 232 Adapter #28030. It uses the FTDI FT232RL chip and drivers. The cables work fine on my XP Pro machine w/SP2.
Jim

[fpreston]

I tried a serial to USB adapter at first. (My Cassiopeia was using my only standard serial port). I couldn't get the JP1.2 to work. Even swapping to the real serial port didn't help. I had to disable the ActiveSync connection to it first and reboot.

Now, I use the USB adapter for my ActiveSync (to save swapping cables), but it still interferes with the JP1.2 when activated.

Fred