# Known issues

The faults in the gripper's firmware and in the software that drives it that are known and not yet fixed, and
what to do until they are. The gripper has no firmware of its own: these are the Spectral Micro driver's, in
gripper mode. The pages that describe each part say the same where it matters; this page collects them in one
place. Which versions work together is in [Versions and compatibility](https://docs.source-robotics.com/SSG48-gripper-docs/2/appendix/compatibility/).

### Spectral driver firmware

Seen in: 107.

| | What happens | What to do | More |
|---|---|---|---|
| KI-1 | A gripper E-stop raises the E-stop error again at every control cycle for as long as the last gripper command carries the E-stop bit, so Send_Clear_Error (or `#Clear`) seems to do nothing. | Send a gripper command with the E-stop bit at 0 and the action bit at 0 (or `#Gripstop 0`), then clear. | [Errors and recovery, clearing](https://docs.source-robotics.com/SSG48-gripper-docs/2/06-operation/errors/#clearing) |
| KI-2 | The answer to a full Send_gripper_data_pack is sent before the gripper acts on the command, so it carries the state from before it. | Ignore that answer; poll with empty frames, and give a move about 100 ms before you trust its object detection. | [Over CAN, host checklist](https://docs.source-robotics.com/SSG48-gripper-docs/2/06-operation/can/#host-checklist) |
| KI-3 | A full gripper command or a clear sent during the gripper calibration ends it, and the gripper stays uncalibrated. The routine's counters are not reset, so the next calibration starts where the stopped one was (it can skip the opening) and counts the time already spent towards its 30 s limit. | Send only empty frames until the calibrated bit is 1. If a calibration was stopped, calibrate again and check the bit; if it does not come, switch the gripper off and on and calibrate. | [Over CAN, host checklist](https://docs.source-robotics.com/SSG48-gripper-docs/2/06-operation/can/#host-checklist) |
| KI-4 | The action status in the gripper's answer is the action bit of the last command; the firmware never clears it, neither at the end of a move nor in the calibration. | Follow a move by its object detection and the position, not by the action status. | [The gripper's state byte](https://docs.source-robotics.com/SSG48-gripper-docs/2/reference/errors/#the-grippers-state-byte) |
| KI-5 | The motor calibration (`#Cal`) sets the driver's current limit to 1600 mA and leaves it there, and `#Save` stores it. Gripper moves are not affected, they use each command's current; the driver's own modes, such as the current and position modes of the teleoperation guide, run with up to 1600 mA. | On a self-built gripper, set `#Ilim` (1000 mA, the default, suits the GBM5208-75) after `#Cal` and before `#Save`. | [Driver setup and first run, current limit](https://docs.source-robotics.com/SSG48-gripper-docs/2/build/first-run/#current-limit) |
| KI-6 | With braking in idle switched on (Send_Settings, or `#Brake 1`), the current that turning the motor drives through its shorted phases is not limited, and the setting is not saved; the gripper coasts again after every power-up. | Leave the default, coasting, unless you need the brake; set it again after each power-up, and do not force the jaws by hand while it brakes. | [Send_Idle](https://docs.source-robotics.com/SSG48-gripper-docs/2/reference/can/system/#send_idle) |

### Python library (Spectral-BLDC)

Seen in: 1.20.

| | What happens | What to do | More |
|---|---|---|---|
| KI-7 | `gripper_object_detection` has its two bits swapped: the library reports 1 where the gripper sends 2 (object found while opening) and 2 where it sends 1 (object found while closing); 0 and 3 are right. | Swap 1 and 2 in your program, or test for "1 or 2" when any object will do. | [With Python](https://docs.source-robotics.com/SSG48-gripper-docs/2/06-operation/python/) |

### PAROL6 Python API (parol6)

Seen in: 0.9.1.

| | What happens | What to do | More |
|---|---|---|---|
| KI-8 | In `rbt.tool.status()`, `engaged` is always true (it is read from the speed field, which the robot always reports as 1), and `part_detected` reads bits 3 and 2 of the gripper's state byte, the temperature and timeout errors, not the object detection in bits 5 and 4. | To know that a part is held, check the position the jaws stopped at, or use a sensor. | [On PAROL6 and PAR6, driving it](https://docs.source-robotics.com/SSG48-gripper-docs/2/06-operation/robots/#driving-it) |
| KI-9 | `rbt.tool.calibrate()` counts the calibration done after a fixed 2 s without reading the calibrated bit, and the SSG-48 takes about 3 s, longer when the jaws start far from the open end. The API has no action to clear a gripper error. | Wait for the calibration before the first move, as the example on the PAROL6 page does; clear an error in the commander's Gripper tab or with Motor GUI, then calibrate. | [On PAROL6 and PAR6, driving it](https://docs.source-robotics.com/SSG48-gripper-docs/2/06-operation/robots/#driving-it) |

## Something that is not here

Check [Troubleshooting](https://docs.source-robotics.com/SSG48-gripper-docs/2/09-troubleshooting/) first. If it is still not explained, [Report a problem](https://docs.source-robotics.com/SSG48-gripper-docs/2/support/report-a-problem/)
says what to include so it can be reproduced. A fixed issue stays on this page, under "Fixed", with the version
that fixes it.