1.8.2 Preset Value of Encoder
The @AAPN(data) can be used to set the preset value of
encoder. The preset value is saved in the EEPROM. When the
power is turn ON, the preset value will be loaded from
EEPROM and set to the start value of encoder.
For 7083B, the current encoder value will save to the preset
value in EEPROM when power is turn OFF. When the power is
next turn ON, the preset value will be re-load from EEPROM.
That it to say, the encoder value is
nonvolatile
even if the
power is OFF. 7083B can set L-bit to 0 to disable the
nonvolatile logic
, Refer to Sec 1.6.6 for more information.
For 7083, there is no
nonvolatile logic
,
so the start value of
encoder is always as same as the preset value in EEPROM. The
L-bit of 7083 is don’t care.
1.8.3 Encoder Counting Sequence
The encoder is a 32-bit Up/Down counter without overflow.
The 0x00000000 will change to 0xffffffff if one down counting
is received. The 0xffffffff will change to 0x00000000 if one up
counting is received. There is no overflow condition.
1.8.4 XOR Control Bit Setting
The internal logic is designed for active high. So the XOR
control bit should be set to 1 in most of application. If the input
signal is single-ended & active high (Sec. 1.5.2), the XOR bit
has to be set to 0 for proper operation.
If the XOR bit is setting error, the encoder value will have
different errors. Refer to Sec. 1.1 for more information.
I-7083/7083D/7083B/7083BD User Manual (V 1.1, Dec/2007) ------------------ 22
