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GR716-DS-UM, May 2019, Version 1.29
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GR716
SPIM_SCK &
SPIM_SEL
This pin together with the pin SPIM_MOSI selects which source the LEON3FT microcontroller should
boot from:
When copy ASW boot from external source is selected (SPIM_MOSI is low)
"00" - Copy software image from SPI Memory
"01" - Copy software image from external SRAM
"10" - Copy software image from external ROM
"11" - Copy software image from external I2C
When boot from external source is selected (SPIM_MOSI is low)
"00" - Boot from SPI Memory
"01" - Boot from external SRAM
"10" - Boot from external ROM
"11" - Unused
Enable for remote access interfaces (SPIM_MOSI is high)
"00" - SPI remote access
"01" - SpaceWire RMAP enable
"10" - I2C remote access
"11" - UART remote access
Note 1:
User should use weak pull-up/pull-downs for configuration of the GR716 microcontroller. A weak
resistor is defined as resistor which require low current from the drive circuitry. The resistance should
be greater or equal to 10K ohm.
Note 2:
Bootstrap signals determine state of GR716 microcontroller after reset has been released.
Note 3:
The LEON3FT processor is always enabled after reset has been released.
Note 4:
Remote access request will force the processor to power down according to 16.2.16 after initialization
has been completed.
Note 5:
Remote access will enable clocks according to table:
1. SpaceWire option will enable SpaceWire core and external SpaceWire interface
2. SPI option will enable SPI for Space Slave and external SPI for Space interface
3. I2C option will enable I2C2AHB bridge and external I2C interface
4. UART option will enable AHBUART1 and external UART interface
Note 6:
Only requested memory interface will have clock and pins enabled.
Note 7:
Watchdog timer will always be enabled and not controllable from bootstraps.
Table 30.
Bootstrap signals
Pin
Functional description