M-Boot ROM Description
587
SPRUHE8E – October 2012 – Revised November 2019
Copyright © 2012–2019, Texas Instruments Incorporated
ROM Code and Peripheral Booting
M-Boot ROM modifies the dividers as shown in
for all the reset types that pull external reset
input to reset the master subsystem, except for a debugger reset or software reset. Refer to the Resets
section in the
System Control and Interrupts
chapter for further discussion.
NOTE:
Configuring the above dividers make a master subsystem and control subsystem RUN at the
same frequency which is equal to MAINOSC frequency selected by user. So users should be
aware of this fact while selecting a MAINOSC clock frequency. Remember that PLL is by
passed during normal boot.
6.5.9 M-Boot ROM GPIO Assignments for Each Boot Mode
The table below gives information on the GPIOs used for each boot mode on M-Boot ROM. More details
on the boot mode are provided further in this document.
Table 6-5. M-Boot ROM Boot Mode GPIO Assignments
M-Boot ROM
Boot Mode
Peripheral
Boot
Function
Name for pin
Direction
GPIO(s) used
Pin Mux Assignment
Peripheral
Mode
Alternate
Mode
Core Select
Serial Boot
Mode
UART0
UART0_RX
Input
PA0_GPIO0
1
0(default)
Master(default
)
(boot mode 2)
UART0_TX
Ouput
PA1_GPIO1
1
0(default)
Master(default
)
I2C0
I2C0_CLK
Input
PB2_GPIO10
1
0(default)
Master(default
)
I2C_DATA
BI-Directional
PB3_GPIO11
1
0(default)
Master(default
)
SSI0
SSI0_CS
Input
PA3_GPIO3
1
0(default)
Master(default
)
SSI0_CLK
Input
PA2_GPIO2
1
0(default)
Master(default
)
SSI0_TX
Output
PA5_GPIO5
1
0(default)
Master(default
)
SSI0_RX
Input
PA4_GPIO4
1
0(default)
Master(default
)
Parallel Boot
Mode
GPIO (s)
D0
Input
PA0_GPIO0
0(default)
0(default)
Master(default
)
(boot mode 0)
D1
Input
PA1_GPIO1
0(default)
0(default)
Master(default
)
D2
Input
PA2_GPIO2
0(default)
0(default)
Master(default
)
D3
Input
PA3_GPIO3
0(default)
0(default)
Master(default
)
D4
Input
PA4_GPIO4
0(default)
0(default)
Master(default
)
D5
Input
PA5_GPIO5
0(default)
0(default)
Master(default
)
D6
Input
PB0_GPIO8
0(default)
0(default)
Master(default
)
D7
Input
PB1_GPIO9
0(default)
0(default)
Master(default
)
HOST_CTRL
Input
PE3_GPIO27
0(default)
0(default)
Master(default
)
DSP_CTRL
Ouput
PE2_GPIO26
0(default)
0(default)
Master(default
)
CAN Boot
Mode
CAN0
CAN0_RX
Input
PB4_GPIO12
5
0(default)
Master(default
)