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58
DMx820 User’s Manual
Field
Description
DIFF
Selects single-ended or differential mode
’0’ = Single Ended. Only “+” inputs are used
’1’ = Pseudo-Differential
FILTER
Enable the input filter
’0’ = Filter is disabled
’1’ = Filter is enabled
JOIN
Used to join the two channels into a single 32 bit counter.
When the channels are joined, only the Channel A
inputs are used.
’0’ = Channels are independent
’1’ = Channels are joined.
IDX_EN
Index Enable: When enabled, a high input on the Index input
clears the counter
’0’ = Index Inputs Disabled
’1’ = Index Input Enabled
HOLD
Register Hold: When enabled, the encoder continues
counting in the background, but the VALUE registers
remain constant.
’0’ = VALUE registers are not held
’1’ = VALUE registers are held
ENA
Enable for this incremental encoder
’0’ = Encoder is disabled
’1’ = Encoder is enabled
INCENCn_VALUEy
Returns the current value of this incremental encoder channel. When INCENCx_MODE[JOIN] = 1, INCENCx_VALUEB contains the most
significant word, and INCENCx_VALUEA contains the least significant word. A 16 bit read should be used to read this register when not joined
(INCENCx_MODE[JOIN] = 0), and a 32 bit read should be used when joined (INCENCx_MODE[JOIN] = 1). Otherwise, the value can change
between read operations. Another option is to set INCENCx_MODE[HOLD] = 1, read the contents of the register, and then set
INCENCx_MODE[HOLD] = 0.
This register can only be written to when INCENCx_MODE[ENA] = 0. This allows the counter to be pre-loaded with a known position value.
15
0
VALUE[15:0]
R(W),+0
Field
Description
VALUE[15:0]
The current value of this incremental encoder channel.