Datasheet
TMC4361A Datasheet | Document Revision 1.22 • 2017-JAN-12
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© 2015 TRINAMIC Motion Control GmbH & Co. KG, Hamburg, Germany — Terms of delivery and rights
to technical change reserved. Download newest version at: www.trinamic.com .
Read entire documentation; especially the “Supplemental Directives” on page 224.
MAIN MANUAL
Because SPI current data is transmitted, the automatic switchover from microsteps to
fullsteps and vice versa entirely depends on the internal ramp velocity.
In order to activate automatic switchover between microstep and fullstep
operation, do as follows:
Action:
Set
FS_VEL
register 0x60 according to absolute velocity [pps] at which the
switchover should happen.
Set
fs_en
= 1 (bit19 of
GENERAL_CONF
register 0x00).
Result:
Now, current values are switched to fullstep values, in case |
VACTUAL
| ≥
FS_VEL
.
A switchback from fullsteps to µsteps is executed in case |
VACTUAL
| <
FS_VEL
.
The status bit
FS_ACTIVE
is set active as long as fullstep mode is enabled and
activated.
During S/D mode, switchover from microsteps to fullsteps and vice versa is only
executed directly by TMC2130. Therefore, a fullstep velocity must only be defined in
TMC2130. TMC4361A transfers microsteps whether TMC2130 is operating in fullstep
or microstep mode.
TMC4361A provides features that change the current scaling automatically, which is
explained in chapter 11, page 120. Stepper motor drivers that are supported by SPI
current datagrams are automatically scaled via current datagrams. To automatically
scale the current of a connected TMC2130 motor stepper driver in S/D mode,
TM4361A sends auto-generated cover datagrams by altering the CS value of the
TMC2130 IHOLD_IRUN register.
In order to activate automatic current scaling for TMC2130 in S/D mode:
Action:
Set
scale_val_transfer_en
= 1 (bit5 of
SPI_OUT_CONF
register 0x04).
Set scale value register 0x06 and scale configuration register 0x05 according to
your requirements (see chapter 11, page 120).
Result:
When current scaling is adapted internally, TMC4361A sends cover datagrams to
TMC2130 automatically, which changes the CS bit directly.
Presettings of the IHOLD_IRUN register of the TMC2130 – executed before via cover
datagrams – are considered whenever the particular register is overwritten with a
newly assigned current scaling value.
i Please consider that the IRUN and IHOLD values consist of 5 bits only. Therefore,
scaling values in register 0x06 must also be adapted to 5-bit values.
TMC2130 SPI
Mode: Automatic
Fullstep
Switchover
TMC2130 S/D
Mode: Automatic
Fullstep
Switchover
TMC 2130 S/D
Mode: Changing
current Scaling
Parameter