L6474 datasheet(33/51 Pages) STMICROELECTRONICS

33 / 51 page

L6474

Programming manual

Doc ID 022529 Rev 2

33/51

9.1.1

ABS_POS

The ABS_POS register contains the current motor absolute position in agreement to the

selected step mode; the stored value unit is equal to the selected step mode (full, half,

quarter, etc.). The value is in 2's complement format and it ranges from -221 to +221-1.

At power-on the register is initialized to “0” (HOME position).

9.1.2

EL_POS

The EL_POS register contains the current electrical position of the motor. The two MSbits

indicate the current step and the other bits indicate the current microstep (expressed in

step/128) within the step.

When the EL_POS register is written by the user the new electrical position is instantly

imposed. When the EL_POS register is written its value must be masked in order to match

with the step mode selected in the STEP_MODE register in order to avoid a wrong

microstep value generation (see paragraph 9.1.10); otherwise the resulting microstep

sequence is incorrect.

Any attempt to write the register when the outputs are enabled causes the command to be

ignored and the NOTPERF_CMD flag to rise (see paragraph 9.1.13).

9.1.3

MARK

The MARK register contains an absolute position called MARK, according to the selected

step mode; the stored value unit is equal to the selected step mode (full, half, quarter, etc.).

It is in 2's complement format and it ranges from -221 to +221-1.

9.1.4

TVAL

The TVAL register contains the current value that is assigned to the torque regulation DAC.

The available range is from 31.25 mA to 4 A with a resolution of 31.25 mA, as shown in

Table 2.

h19

STATUS

Status

XXXX (2)

High impedance state,

UVLO/Reset flag set.

h1A

RESERVED

Reserved address

h1B

RESERVED

Reserved address

R: Readable, WH: writable only when outputs are in high impedance, WR: always writable.

According to startup conditions.

Table 9.

Registers map (continued)

Address

[Hex]

name

Len. [bit]

Reset

Hex

Reset Value

Remarks

(1)

Table 10.

EL_POS register

Bit 8

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

STEP

MICROSTEP

L6474 数据表(PDF) 33 Page - STMicroelectronics

L6474 数据表(HTML) 33 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51

数据表下载