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Since the mikro-click modules operate at 3.3 V power supply, the CPLD enables the level translator, SN74AVC2T245 (from Texas)
to translate 1.8 V to 3.3 V voltage for the selected module.
The following table describes configuration for accessing mikro-click modules on mikroBUS1 or mikroBUS2 through SPI3/UART2/
PWM interface.
Table 21. SPI3/UART2/PWM selection on mikro-click modules
CPLD signals
Registers
Configuration
CFG_MUX_uBUS1_SPI_B
CFG_MUX_uBUS2_SPI_B
BRDCFG3[6]
0: SPI3 routed to mikroBUS1 module.
1: SPI3 routed to mikroBUS2 module.
CFG_MUX_UART2_SEL0
CFG_MUX_uBUS1_UART_B
CFG_MUX_uBUS2_UART_B
BRDCFG3[5:4]
0X: UART2 routed to RS232 transceiver and
DB9 connector P1A (default).
10: UART2 routed to mikroBUS1 module.
11: UART2 routed to mikroBUS2 module.
CFG_MUX_uBUS1_PWM_B
CFG_MUX_uBUS2_PWM_B
BRDCFG3[7]
0: PWM (FTM1_CH1) routed to mikroBUS1
module.
1: PWM (FTM1_CH1) routed to mikroBUS2
module.
Also, the mikro-click modules on mikroBUS1 or mikroBUS2 can be accessed directly through I2C1 channel 6 or channel 7,
respectively.
2.18 GPIOs
The GPIOs used on the LS1028ARDB are GPIO1_DAT[24], GPIO1_DAT[25], and GPIO3_DAT[2:4]. Apart from these GPIOs, all
signals (UART, SPI, PWM) coming on connectors (mikro-click module) can also act as GPIO signals.
GPIO1_DAT24 controls output voltage of the VDD and TA_BB_VDD regulators. It is used to change the VDD/TA_BB_VDD value
from 1.0 V to 0.9 V as described in the following table.
Table 22. GPIO1_DAT[24] setting
GPIO
Setting
VDD/TA_BB_VDD
GPIO1_DAT24
High (default)
1.0 V
GPIO1_DAT24
Low
0.9 V
GPIO3_DAT[2:4] connects to the CPLD and the CPLD has provision to control/monitor the GPIO through registers. For more
information, see BRDCFG3 register detail in
on page 58.
The CPLD combines all the interrupts received from the board devices and sends out the interrupt signals to the LS1028A
processor using GPIO1_DAT25.
2.19 Interrupt handling
All interrupts coming from all devices on LS1028ARDB are communicated to the LS1028A processor through GPIO1_DAT25.
The following are the interrupt assignments:
GPIOs
QorIQ LS1028A Reference Design Board Reference Manual, Rev. b, 11/2018
NXP Semiconductors
COMPANY CONFIDENTIAL
43
Содержание QorIQ LS1028A
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