Firmware User Manual (AE-step)
10
Revision 1.02
2019-04-24
TLE984x Firmware User Manual
BootROM Startup procedure
A list of supported boot mode pin selections is given in
.
Many of the called initialization parts require further configuration parameters which are stored in the NVM CS
(Configuration Sector).
The initialization process differs slightly between each selected boot mode. Each boot mode has a different
set of initialization steps to be performed. For instance, some initialization steps might be skipped for one
mode but carried out for another mode.
The functional blocks are listed in
.
3.2
Boot Modes
The different BootROM-supported boot modes are listed in
Table 3-2 “BootROM Boot Modes” on Page 10
.
These boot modes are pin-latched during reset release. The mode decides which initialization parts are to be
executed by BootROM.
3.3
Debug Support Mode entry (with SWD port)
Debug support mode is available for SWD. The BootROM starts the overall device initialization as described in
“Startup Program Structure” on Page 9
.
The BootROM then enters a waiting loop to synchronize with the debugger connected to the Serial Wire Debug
(SWD) interface. After that, the BootROM finishes the boot process and starts to execute user code under
control of the debugger.
Firmware ensures that jumping to user code in user mode entry or customer debug entry is performed with
identical RAM and SFR content, except WDT1.
Table 3-1 Functional Blocks
Block
Description
Reference
Watchdog Disable The WDT1 is disabled, depending on the boot mode.
RAM MBIST
Performs RAM MBIST (optional).
RAM Init
Inits RAM to zero (mandatory).
MapRAM Init
Inits MapRAM based on MapBlock data
Analog Module
Trimming
Analog module NVM CS trimming values are configured in the hardware.
PLL Init
Switch system clock to PLL
Start NAC Timer
Start a timer which is dedicated to the user mode / BSL “no activity count
timeout” calculation.
BSL
BSL communication
Table 3-2 BootROM Boot Modes
TMS /
SWD_IO
P0.0 /
SWD_CLK
Mode / Comment
0
X
USER_BSL_MODE
User Mode / BSL Mode
1
1
SWD_DEBUG_MODE
Debug Support Mode with SWD port
All other values
Reserved for internal use