Infineon Technologies TC1784, User Manual

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TC1784
BootROM Content
User´s Manual 7-7 V1.1, 2011-05
BOOT_TC1784B, V1.21R12
• Header 0 - Base address A001’FFE0
H
; End address A001’FFFF
H
• Header 1 - Base address A000’FFE0
H
; End address A000’FFFF
H
Any of the Headers is 32 Bytes long, containing information in accordance to Table 10-2 .
In any Alternate Boot Mode always the Header 0 is checked first, and if failed - Header
1 is checked next. Where the check gives OK, the full start address is taken from the
respective Header field STADABMx (index x=0,1 for Header 0,1).
If check fails for both the Headers, the further execution depends on the startup mode
currently configured in HWCFG: a jump either to ASC- or to Generic- (CAN pins)
Bootloader is performed by the SSW.
The validation procedure executes CRC calculation based on a 32-bit polynomial:
f(x) = x
32
+x
26
+x
23
+x
22
+x
16
+x
12
+x
11
+x
10
+x
8
+x
7
+x
5
+x
4
+x
2
+x+1 (7.1)
This calculation is performed by the SSW using the Memory Checker Module in TC1784.
The complete check-procedure for a Header consists of the following steps:
1. check the ABM Header ID at offsets 04
H
..07
H
(the correct values are given in
Table 10-2 ):
a) if OK - continue with 2.
b) if Not - exit the check-procedure for this Header with Error.
2. calculate the CRC of the first 24 Bytes from the ABM Header - process the fields
STADABM...CRCRange at offsets 00
H
...17
H
a) compare the result with the CRChead value (offset 18
H
)
- if OK - continue with 2.b)
- if Not - exit the check-procedure for this Header with Error.
Table 7-2 ABM Headers Structure
Offset
Addr. Size
Byte Field Name Description
00
H
4 STADABM User Code Start Address
04
H
4 ABMHDID ABM Header ID = DEAD BEEF
H
(Confirmation code)
08
H
4 ChkStart Memory Range to be checked - Start Address
0C
H
4 ChkEnd Memory Range to be checked - End Address
10
H
4 CRCrange Check Result for the Memory Range
14
H
4 CRCrange Inverted Check Result for the Memory Range
18
H
4 CRChead Check Result for the ABM Header (offset 00
H
..17
H
)
1C
H
4 CRChead Inverted Check Result for the ABM Header