Delta Tau GEO BRICK LV User Manual
Geo Brick LV User Manual
PinOuts and Software Setup
79
Encoder Count Error (Mxx18)
The Geo Brick LV has an encoder count error detection feature. If both the A and B channels of the
quadrature encoder change state at the decode circuitry (post-filter) in the same hardware sampling clock
(SCLK) cycle, an unrecoverable error to the counter value will result (lost counts). Suggested M-Variable
Mxx18 for this channel is then set and latched to 1 (until reset or cleared). The three most common root
causes of this error:
quadrature encoder change state at the decode circuitry (post-filter) in the same hardware sampling clock
(SCLK) cycle, an unrecoverable error to the counter value will result (lost counts). Suggested M-Variable
Mxx18 for this channel is then set and latched to 1 (until reset or cleared). The three most common root
causes of this error:
Real encoder hardware problem
Trying to move the encoder (motor) faster than it’s specification
Using an extremely high resolution/speed encoder. This may require increasing the SCLK
The default sampling clock in the Geo Brick LV is ~ 10MHz, which is acceptable for virtually all
applications. A setting of I7m03 of 2257 (from default of 2258) sets the sampling clock SCLK at about
~20MHz. It can be increased to up to ~40 MHz.
applications. A setting of I7m03 of 2257 (from default of 2258) sets the sampling clock SCLK at about
~20MHz. It can be increased to up to ~40 MHz.
Note
No automatic action is taken by the Geo Brick LV if the encoder count
error bit is set.
error bit is set.