908E626 Datasheet, PDF (19/38 Pages) Freescale Semiconductor, Inc – Integrated Stepper Motor Driver with Embedded MCU and LIN Serial Communication

FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
RESET INTERNAL SOURCES
Reset Mask Register (RMR)
Autonomous Watchdog
AWD modules generates a reset because of a timeout
(watchdog function).
High-Temperature Reset
To prevent damage to the device, a reset will be initiated if
the temperature rises above a certain value. The reset is
maskable with bit HTRE in the Reset Mask Register. After a
reset the high-temperature reset is disabled.
Low-Voltage Reset
The LVR is related to the internal V_DD. In case the voltage
falls below a certain threshold, it will pull down the RST_A
terminal.
High-Voltage Reset
The HVR is related to the external V_SUP voltage. In case
the voltage is above a certain threshold, it will pull down the
RST_A terminal. The reset is maskable with bit HVRE in the
Reset Mask Register. After a reset the high-voltage reset is
disabled.
RESET EXTERNAL SOURCE
External Reset Terminal
The microcontroller has the capability of resetting the
SMARTMOS device by pulling down the RST terminal.
Register Name and Address: RMR - $06
Bit7 6
5
4
3
2
1 Bit0
Read
0
0
0
0
0
TTEST
HVRE HTRE
Write
Reset 0
0
0
0
0
0
0
0
TTEST — High-Temperature Reset Test
This read / write bit is for test purposes only. It decreases
the overtemperature shutdown limit for final test. Reset clears
the HTRE bit.
• 1 = Low-temperature threshold enabled.
• 0 = Low-temperature threshold disabled.
HVRE — High-Voltage Reset Enable Bit
This read / write bit enables resets on high-voltage
conditions. Reset clears the HVRE bit.
• 1 = High-voltage reset enabled.
• 0 = High-voltage reset disabled.
HTRE — High-Temperature Reset Enable Bit
This read / write bit enables resets on high-temperature
conditions. Reset clears the HTRE bit.
• 1 = High-temperature reset enabled.
• 0 = High-temperature reset disabled.
SERIAL PERIPHERAL INTERFACE
The serial peripheral interface (SPI) creates the
communication link between the microcontroller and the
908E626.
The interface consists of four terminals (see Figure 10):
• SS—Slave Select
• MOSI—Master-Out Slave-In
• MISO—Master-In Slave-Out
• SPSCK—Serial Clock (maximum frequency 4.0 MHz)
A complete data transfer via the SPI consists of 2 bytes.
The master sends address and data, slave system status,
and data of the selected address.
Analog Integrated Circuit Device Data
Freescale Semiconductor
908E626
19