Datasheet

TMC8460-BI Datasheet (V100 / 2016-Sep-01)
Copyright © 2016 TRINAMIC Motion Control GmbH & Co. KG 13
W ATCHDOG
• Configurable for all inputs and outputs
• Outputs will be assigned with configurable level @ watchdog event
• Inputs will trigger a watchdog event only
• ECAT SoF and PDI SPI Chip Select can be monitored with watchdog as well
E MERGENCY S WITCH I NPUT
• If used all functional outputs are set to a configurable safe state when the switch is not actively
driven high
• Low active: must be pulled high for normal operation if used.
2.2 Configuration Options
The TMC8460 must be configured after power-up for proper operation. The EtherCAT part is automatically
configured using configuration data from the connected I2C EEPROM.
The MFCIO block can also be configured using EEPROM configuration data. The EEPROM must therefore
contain additional configuration data with category ‘1’, which is automatically copied to ESC
configuration RAM at addresses 0x0580:0x05FF.
Another way to configure the MFCIO block is to directly write the configuration bits to this RAM area
using the ECAT or the PDI interface.
The MFCIO block can be used directly by a local application controller independent of the EtherCAT data
path. Therefore, no upfront configuration is required since the MFCIO blocks comes with a dedicated
SPI interface allowing complete access to its functions and local register set.
2.3 Control Interfaces
2.3.1 Ethernet Interface
For connection to the Ethernet physical medium and to the EtherCAT master, the TMC8460-BI offers two
MII ports (media independent interface) and connects to standard 100Mbit/s Ethernet PHYs or 1Gbit/s
Ethernet PHYs running in 100Mbit/s mode.
2.3.2 Process Data Interface
The Process Data Interface (PDI) is an SPI interface. The TMC8460-BI provides an SPI slave interface with
ca. 30Mbit/s to connect to a local MCU or application controller. Typically, the local application controller
contains the EtherCAT slave stack to control the EtherCAT state machine and to process state change
requests by the EtherCAT master. Pulling the external configuration pin PDI_EMULATION high switches
to Device Emulation mode. In Device Emulation mode, the TMC8460-BI can be used in standalone mode
without MCU since state change requests by the master are directly forwarded to the state registers
inside the TMC8460’s ESC part. The PDI SPI interface remains active and can be used by an MCU in
device emulation state.
2.3.3 Multi-Function and Control IO Block Interface
The MFCIO block of the TMC8460-BI comes with a dedicated SPI slave interface to allow direct access
from a local application controller. It is called MFC CTRL SPI interface. This interface to the MFCIO block’s
functions is always available even if the EtherCAT state machine is currently not in operational state
(OP). Protocol structure and timing are identical to the PDI SPI.
2.3.4 SPI Bus Sharing
Both SPI interfaces – PDI SPI and MFC CTRL SPI – can share the same SPI bus signals using two chip
select signals. This reduces overall number of signals on the PCB and requires only one SPI interface
on the local MCU. The external configuration pin SHARED_SPI_BUS needs to be pulled high for bus
sharing. In this case, the PDI SPI bus is used as shared bus interface together with the chip select line
of the MFC CTRL SPI interface.