Realtek Ameba-D RTL872 D Series User Manual page 464

31:12 RSVD N/A
11:0 RCC R/W
21.3.2.3 REG_PC

Name: Q-Decoder Position Counter Register

Size: 32 bits

Address offset: 0x0010

Read/write access: read
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Bit Name Access
31:20 RC R
19:18 STA R
17 ALS R
16 DIR R
15:0 PC R
21.3.2.4 REG_ISC

Name: Q-Decoder Index Signal Configuration Register

Size: 32 bits

Address offset: 0x0014

Read/write access: read/write
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User Manual
-- Reserved
0 The value to be compared with the rotation counter. If the rotation counter is equal to this
value then the corresponding interrupt is asserted.
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RC
R
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Default Description
0 The rotation counter

If the index pulse signal is enabled (depending on IDX_EN) and the rotation counter
mode is 0 (depending on RC_MOD), this rotation counter increases or decreases
(depending on the direction, DIR) by 1 on every index pulse.

If the index pulse signal is disabled (depending on IDX_EN) or the rotation counter
mode is 1 (depending on RC_MOD), this rotation counter increases or decreases by 1
for every position counter overflow (+1) or underflow (-1) occurred.
When the rotation counter overflow or underflow occurs, a corresponding interrupt is
asserted.
0 The Q-decoder phase state, current state of (A, B) phase.
0 The status of auto load to set initial phase

1: Auto load done

0: Auto load on-going
If the initial phase auto load is disabled, the value of this bit should be ignored.
0 The movement direction

0: decrease

1: increase
The position accumulation counter
0
Step is +1, -1 or to be reset to 0.
This position counter increases or decreases (depending on the direction) by one for every 1
or 2 (depending on CNT_SC) phase state changes.

If this position counter is equal to maximum position counter (MPC) and the
movement direction is forward, itis reset to 0 on the next counter increment.

If this position counter is equal to 0 and the movement direction is backward, it is reset
to the maximum position counter (MPC) on the next counter decrement.
If the position counter reset on index pulse is enabled (depending on POS_RST_EN), this
position counter is reset to 0 on the index pulse signal.
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PC
R
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Ameba-D User Manual
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STA
R
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© REALTEK 2019. All rights reserved.
17 16
ALS DIR
R R
1 0
1 0