DriveWire

[zephyr]

The diagram below (by Roger Taylor) shows the wiring for the CoCo-to-PC Serial Cable for use with CoCoNet and DriveWire servers. Are the links at pins 4-6 and 7-8 needed if using the cable only for the Drivewire 3/4 server?

[KenH]

Are the links at pins 4-6 and 7-8 needed if using the cable only for the Drivewire 3/4 server?

These links are not required for the Drivewire cable.
For the Dragon the cable should be built according to the instructions in my tutorial here: viewtopic.php?f=5&t=781

For a Drivewire cable for the CoCo, see the attached instructions. Note that the description part which includes Vcc in the cable is incorrect, but the pinout table is correct.
There is also a modified version of the attached CoCo cable wiring in which pins 1 and 2 (CD and RxD) are tied together. This is necessary to achieve the 230 kbps bit rate on the CoCo3, but will also work (but not required) at the lower bit rates.

Ken

[zephyr]

Thanks Ken! I'm going to make a CoCo-to-PC Serial Cable. Why is the transfer rate slower on a CoCo 1 compared to a CoCo 2 (38,400 bps vs 57,600 bps)?

[KenH]

According to Darren A, the CoCo 1 bit banger is limited to 38,400 bps by the 741C opamp used for level translation.

The CoCo 1 uses a 741C opamp in the Data Out circuit of the bit banger
(for RS-232 level translation). That opamp has a slew rate which is
too slow to handle transitions at 57600 bps.

quote from: http://comments.gmane.org/gmane.comp.ha ... coco/39939

[zephyr]

Seems to be true, but its hard to believe that the CoCo 1 hardware is inferior!

[zephyr]

Here is a copy of Drivewire 3 for the CoCo 1, 2, or 3 and Windows. Visit http://www.cloud9tech.com/ for updates, and to download server software for other operating systems.

[KenH]

Steve,
I recommend using Drivewire 4 for the server side (works on Windows/Mac/Linux).
The server side has seen some major improvements. There's no change in the CoCo files (CoCo2 files can also be used with the Dragon in CoCo mode).
Download the latest Drivewire server version here: https://sites.google.com/site/drivewire4/download

[zephyr]

I can't get it to work with my CoCo 1. All I get on the server when I enter DIR on the CoCo is the following log entries.
DW3 server:

2012-12-04 15:14:49 OP_READEX[0] LSN[322] Checksum[65280] Error[243]
2012-12-04 15:15:15 OP_READEX[0] LSN[322] Checksum[65280] Error[243]
2012-12-04 15:15:24 OP_READEX[0] LSN[952] Checksum[65280] Error[243]

DW4 server:

Tue Dec 04 2012 15:13:22.734 INFO DWProtocolHandler dwUIcliIn-41 requesting protocol device reset
Tue Dec 04 2012 15:13:28.875 INFO DWSerialDevice dwproto-0-10 opened serial device COM1
Tue Dec 04 2012 15:13:37.187 WARN DWProtocolHandler dwproto-0-10 Timed out reading from CoCo in OP_READEX
Tue Dec 04 2012 15:13:37.187 WARN DWProtocolHandler dwproto-0-10 OP_READEX took 281ms.
Tue Dec 04 2012 15:13:41.937 WARN DWProtocolHandler dwproto-0-10 Timed out reading from CoCo in OP_READEX
Tue Dec 04 2012 15:13:41.937 WARN DWProtocolHandler dwproto-0-10 OP_READEX took 281ms.

Any ideas as to what could be the problem?

[KenH]

Drivewire transactions have a timeout of 200ms, if the expected response from either side doesn't occur within that window an OP_READEX error is generated.
It is most likely a communications problem.
Probably with the Drivewire cable. Could also be that the wrong baud rate was selected or the PC memory/cpu is overloaded (unlikely).
If you have access to another PC / laptop you should give that a try.
Do you have a serial port on your PC or are you using a USB-serial adapter?

If all fails, enable the advanced logging options on the DW4 server, generate some errors and file a bug report to Aaron Wolfe through the DW4 menu.
Aaron has been very helpful helping me diagnose problems with the Dragon Drivewire setup.

[zephyr]

I have triple checked the cable wiring with the diagram you posted. Also checked for continuity with a multimeter.

I'm not using a USB adapter. My PC has a serial port set as COM1.