Several builders have asked about setting the speed on the Silent Shield Clock Controller used in several of the stepper motor desk clocks. This post will try to summarize everything a single post. Feel free to ask questions in this post. I may condense the threads to bring the important information to the top.
The Silent Shield Clock Controller (available on Etsy) includes the bare minimum components needed to control my stepper motor desk clocks. This includes an Arduino Nano, TMC2208 stepper motor driver, DS3231 real time clock module, and a small circuit board to connect the components. Four small jumper blocks can be added or removed to select various motor speeds and debug modes.
The first iteration of the clock used a commonly availably board called a CNC Shield V4 to provide the same functionality as the Silent Shield Clock Controller. Its primary advantage is that it is commonly available worldwide without high shipping charges for postage from the US. It uses the same electronic components with the same algorithm programmed into the Arduino Nano. Speed settings also use four small jumper blocks with the same configuration as the Silent Shield Clock Controller.
The latest speed setting is selected according to the following table that is used by the latest algorithm that is accurate as of 11-May-23. The table may change over time as new clocks are designed, so double check the assembly notes that come with your clock and download the latest algorithm from the clock description page on this web site.
The most current algorithm supports the six different speed settings used in four different clocks. The jumpers select the speed. For example, the SP10 clock with 400 step motors uses setting number 2 with a jumper setting of 0010. This corresponds to jumpers from left to right that are "out", "out", "in", and "out".
Here are pictures of both style of boards showing speed setting number 2 with jumpers set to 0010.
The Silent Shield Clock Controller uses four out of the five available jumper positions as shown below with yellow highlights. The fifth jumper at the far-left position is not used. This picture is showing the 0010 configuration.
The jumper pin locations for the CNC Shield V4 are located here. This picture is also showing the 0010 configuration.