# sinqmotor

## Overview

This library offers base classes for EPICS motor drivers (`sinqAxis` and `sinqController`) of PSI SINQ. These classes are extensions of the classes `asynMotorAxis` and `asynMotorController` from the `asynMotor` framework (https://github.com/epics-modules/motor/tree/master/motorApp/MotorSrc) and bundle some common functionalities.

## Features

sinqMotor offers a variety of additional methods for children classes to standardize certain patterns (e.g. writing messages to the IOC shell and the motor message PV). For a detailed description, please see the respective function documentation in the .h-file. All of these functions can be overwritten manually if e.g. a completely different implementation of `poll` is required

### sinqController
- `stringifyAsynStatus`: Convert the enum `asynStatus` into a human-readable string.
- `errMsgCouldNotParseResponse`: Write a standardized message if parsing a device response failed
- `paramLibAccessFailed`: Write a standardized message if accessing the parameter library failed

### sinqAxis
- `atFirstPoll`: This function is executed once before the first poll. If it returns anything but `asynSuccess`, it retries.
- `poll`: This is a wrapper around `doPoll` which performs some bookkeeping tasks before and after calling `doPoll`:

  Before calling `doPoll`:
  - Try to execute `atFirstPoll` once (and retry, if that failed)

  After calling `doPoll`:
  - Reset `motorStatusProblem_`, `motorStatusCommsError_` and `motorMessageText_` if `doPoll` returned `asynSuccess`
  - Run `callParamCallbacks`
  - Return the status of `doPoll`
- `doPoll`: This is an empty function which should be overwritten by concrete driver implementations.

## Versioning

The versioning is done via git tags. Git tags are recognized by the PSI build system: If you tag a version as 1.0, it will be built into the directory /ioc/modules/sinqMotor/1.0. The tag is directly coupled to a commit so that it is always clear which source code was used to build which binary.

All existing tags can be listed with `git tag` in the sinqMotor directory. Detailed information (author, data, commit number, commit message) regarding a specific tag can be shown with `git show X.X`, where X.X is the name of your version. To create a new tag, use `git tag -a X.X`. If the tag `X.X` is already used by another commit, git will show a corresponding error.

## How to build it

The makefile in the top directory includes all necessary steps for compiling a shared library together with the header files into `/ioc/modules` (using the PSI EPICS build system).Therefore it is sufficient to run `make install -f Makefile` from the terminal.

To use the library when writing a concrete motor driver, include it in the makefile of your application /library the same way as other libraries such as e.g. `asynMotor` by adding `REQUIRED+=sinqMotor` to your Makefile.