USB communication failures can be caused by a myriad of things, including incorrect operating system settings, USB hardware conflicts, incorrect software configuration, or hardware failures.
Note that this article is primarily intended to help isolate USB communication issues with Paramount Robotic Telescope mounts, but may be helpful troubleshooting communication issues using other USB devices, including, but no limited to, cameras, focusers, filter wheels, weather stations, and dome controllers.
Double-check the power source. Intermittent power (for example, from a failed web power switch, undercharged battery, shorted power supply unit cable) results in power loss to the mount, and may cause USB to mount communication failures. As a test, temporarily plug the Paramount power supply unit directly into a tested electrical socket "on the grid" (removal all uninterrupted power supplies, power inverters, batteries, solar-powered power sources, etc.) to see if the behavior persists.
If TheSkyX successfully establishes connection the Paramount mount, but, upon
issuing the Find Home command from TheSkyX (not from the hand paddle), or
issuing any mount slew or motion command results in a "Receive Timeout.
COMM_TIMEOUT. Error: 21002." error message, followed by "Device:
Mount error, poor communication, connection automatically terminated.
Error = 213" message, one or both of the MKS 5000 motors has not been
properly initialized when the mount was turned on.
When the motor or motors cannot be initialized, the control system provides
the following feedback::
Motor initialization failure most commonly occurs when:
The Paramount's USB hub requires power through the USB cable (so that it can be USB 2.0-compliant). The Windows operating system's Selective Suspend feature can suspend power to USB devices, rendering USB 2.0-compliant devices that are connected to the computer inoperable. See Software Bisque Technical Support Article Number 1236 for details how to resolve this Windows operating-system issue that can cause USB communication failures.
Driver-level USB3 conflicts with USB2 on the computer can result in USB communication failures. Consult your computer's documentation for instructions how to disable USB3 from BIOS to see if the behavior persists. Related article.
Corrosion on cables, connectors, and ports on devices that are left outside for extended periods of time can cause unreliable USB communication. Use a commercial electronics spray cleaner on all the cable connectors and ports.
Use the process of elimination to isolate communication errors by doing the following daytime, bench (using the most basic, possible mount configuration):
For Paramount mounts, check that the physical USB port is not bent, or otherwise damaged, and that the USB connector is soldered to the MKS 5000 control board.
When the Paramount is plugged in, turned on, and connected directly to a computer using a 15-foot or shorter USB cable, the operating system must recognize the MKS 5000 internal hub.
When the Paramount is plugged in, turned on, and connected directly to a computer running a native operating system (no VMs, remote desktop, or VNC) using a 15-foot or shorter USB cable, provided the latest MKS 5000 USB driver is installed, the Software Bisque MKS 5000 must be listed under Ports (COM & LPT) in the Windows Device Manager (see screen capture below).
When the Paramount is plugged in, turned on, and connected directly to a computer running macOS using a 15-foot or shorter USB cable, the Hardware Report (Apple > About this Mac > System Report button > Hardware > USB) reports the MKS 5000 as a USB Hi-Speed Bus (see screen capture below) with the Product Identifier (PID) of 0x1338, and the Vendor Identifier (VID) of 0x2527.
After performing Steps 1-6, and using the hardware configuration described above, if the operating system still does not recognize the MKS 5000 USB hub, the MKS 5000 UART component may have failed, and the MKS 5000 needs replaced. See the Replacement Procedure links at the bottom of this article to proceed with the replacement.
Dangling cables can become snagged or loose over time, resulting in unreliable communication. Ensure the USB cabling remains plugged in at all times by adding some type of cable strain relief (such as velcro straps) to prevent unwanted movement of the USB cable that is attached to the device. See this post for a suggested intermediate cable to reduce strain on the mount's USB port.
USB ports (and all external ports and connectors on all equipment) can become corroded over time, especially in brackish environments. Corrosion can cause intermittent or unreliable USB communications and other problems.
Software Bisque recommends performing periodic, thorough cleaning of all the connectors and components using an electrical contact cleaner (for example, WD-40 Electrical Contact Spray Cleaner) to avoid these issues.
If you are uncomfortable, or unable to perform any of the above troubleshooting steps, consider returning the mount or MKS 5000 board to Software Bisque for diagnosis and service (if necessary).
See the following links for details how to proceed:
Return Paramount for Service Procedure | Warranty Replacement Procedure | Non-Warranty Replacement Procedure
SBKB;communication errors; error; 21002; USB; poor communications
Last Reviewed: 2019-04-01
Daniel R. Bisque
Software Bisque, Inc.
862 Brickyard Circle
Golden, Colorado 80403-8058
Office Hours: 8 a.m.-5 p.m. Monday-Friday GMT-7:00
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