SD21 Servo Mid Position

We are pleased to announce that we have worked with Devantech to produce an updated firmware for the SD21 (part AXE031) 21 channel servo driver with an updated command to save all the current servo position values as the default power up positions.

So bascially you set up all servos to their desired power up position and then issue the special command

- writei2c 126,(90)

This saves the current values as the default power up values. This saving takes about 200ms to do, during which time the servos will not be driven and so may 'twitch' once.

For this command you require firmware version 7 or later. You can check the firmware value by reading register 64.

- readi2c 64,(b1)
- debug

All new units will now be sold with this firmware upgrade. If you have an old firmware version we are offering a 'chocolate bar' upgrade.

Post us your old SD21 (to the Bath Business Park address) with a chocolate bar and your return address and we we will reprogram the SD21 and return (minus the chocolate bar, which will naturally be eaten by the person doing the reprogramming!).