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GR716-DS-UM, May 2019, Version 1.29
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www.cobham.com/gaisler
GR716
2.7.3
External ADC and DAC interface
The number of pins used for the external ADC and DAC interface depends upon the number of exter-
nal ADC and DAC channel the application shall support. The interface can use up to 8 address lines in
order to address and control multiple ADC and DAC outside the GR716 microcontroller. On the other
hand, if very few or only one ADC or DAC is used the 8 address lines can be assigned to another sys-
tem interface.
2.8
I/O switch matrix pin validation script
This an introduction to the validation script provided upon request in order to validate pin configura-
tions and to generate constants for the I/O switch configuration registers. The intention of the script is
to help the user of the GR716 microcontroller to validate a configuration according to table 2.6 and to
quickly setup a system for test. The script should not be used for any other purpose than test and
debug of systems using the GR716 microcontroller.
2.8.1
Functional pin mapping sections
The I/O configuration script is written in TCL and contains lists for mapping functional pins to physi-
cal pins on the GR716 microcontroller as described in table 2.6. Each functional group maps individ-
ual functional pins to physical external pins. Example of UART0 configuration description are shown
in table 16.
Table 16 specifies the following for the configuration UART0_CFG0:
•
functional pin UART_CTSN(0) of UART0 to mapped to external physical pin GPIO(0)
•
functional pin UART_RTSN(0) of UART0 to mapped to external physical pin GPIO(1)
•
functional pin UART_TX(0) of UART0 to mapped to external physical pin GPIO(2)
•
functional pin UART_RX(0) of UART0 to mapped to external physical pin GPIO(3)
Functions can have multiple I/O configurations and are then differentiated by adding a consecutive
number to the name of the configuration. All interface options described in table 2.6 are described in
the I/O mux script.
2.8.2
I/O configuration sections
The I/O configuration section specifies all functional groups to be available on physical pins. The
functions and configurations are listed and named in this section. Example of using UART0, UART1
and UART3 are listed in table 16.
Table 16.
UART0 functional pin mapping to external pins of the GR716 microcontroller
set uart0_cfg0 { {uart0_cfg0} {
{ 1 1 uart_ctsn(0) in}
{ 0 1 uart_rtsn(0) out}
{ 2 1 uart_tx(0) out}
{ 3 1 uart_rx(0) in}
} }
Table 17.
Example of mapping UART0, UART1 and UART2 to external pins of the GR716 microcontroller
set iomx_uart0_cfg [list \
$auart_cfg0 $uart2_cfg0 $uart3_cfg1 \
]