TMC428 ETC-unknow, TMC428 Datasheet - Page 9

• Manufacturer Part Number: TMC428
• Description: Intelligent Triple Stepper Motor Controller With Serial Peripheral Interfaces
• Manufacturer: ETC-unknow

TMC428 DATA SHEET (V. 1.00 / February 12, 2001)
The signal nSCS_C has to be assigned at least three clock cycles (tSUCSC) high before sending a 32 bit
datagram. To initiate a transmission, the signal nSCS_C has to be set to low. Three clock cycles later
(tHDCSC) the serial data clock may go low. The most significant bit (MSB) of a 32 bit wide datagram
comes first and the least significant bit (LSB) is transmitted as the last one. To complete the data
transmission the serial data clock SCK_C has to set to high first and at least three clock cycles later, the
signal nSCS_C has to be assigned to high. So, nSCS_C and SCK_C change in opposite order from low to
high at the end of a transmission as these signals change from high to low at the beginning.
Automatic Power-On Reset
The TMC428 performs an automatic power-on reset (see ). To be sure, that the power-on reset has been
completed before starting communication with the TMC428, one should wait at least for 10 µs before
sending the first datagram, which is approximately one datagram at 16 MHz clock frequency
(tDATAGRAM16MHzMin = (1+32+1) * 6 / 16 MHz = 12.75 µs).
Serial Peripheral Interface to Stepper Motor Driver Chain
The timing of the serial stepper motor interface is similar to that of the micro controller interface. It
directly connects to SPI
for each stepper motor driver chip of the daisy chain. From the micro controllers point of view, it simply
sends a fixed sequence of datagrams to the TMC428 to initialize it after power-up. Once initialized by the
micro controller, the TMC428 autonomously generates the datagrams for the stepper motor driver daisy
chain without any additional interventions of the micro controller.
Figure 6: Timing diagram of the serial stepper motor driver interface
Copyright © 2000, TRINAMIC Microchips GmbH
TRINAMIC
M I C R O C H I P S
nSCS_S
SDO_S
SCK_S
SDI_S
CLK
tCLK
tSUSCS
tPD
tHDSCS
TM
smart power stepper motor drivers. The bit mapping is configurable individually
tPD
tCKSL
1 x sampled SDI_S
sdi_s_bit#0
sdo_s_bit#0
tPD
tCKSH
one full stepper motor driver datagram
sdi_s_bit#1
sdo_s_bit#1
tDATAGRAMdrv
m x sampled SDI_S
m datagram bits
sdo_s_bit#n-1
sdi_s_bit#n-1
1 x sampled SDI_S
sdi_s_bit#n
sdo_s_bit#n
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