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Joedubs: /* Memory address lookup */

2022-02-24T20:14:11Z

Memory address lookup

Joedubs: /* Quick Reference */

2020-12-04T02:06:41Z

Quick Reference

Joedubs: /* Helpful links */

2020-11-23T17:04:35Z

Helpful links

Joedubs: /* Helpful links */

2020-11-23T17:03:12Z

Helpful links

Joedubs at 17:03, 23 November 2020

2020-11-23T17:03:05Z

Joedubs: Created page with "= Purpose of this section = =Quick Reference= ==Memory address lookup== Registers a0, a1, a8, and a9 are used as offsets when the code needs to reference different memory..."

2020-11-15T02:26:55Z

Created page with "= Purpose of this section = =Quick Reference= ==Memory address lookup== Registers a0, a1, a8, and a9 are used as offsets when the code needs to reference different memory..."

New page

= Purpose of this section =

=Quick Reference=
==Memory address lookup==
Registers a0, a1, a8, and a9 are used as offsets when the code needs to reference different memory locations.
There's a table in the ECU that sets up those offsets at boot:

<pre>
0000:808835CC movh.a a0, #0xD002
0000:808835D0 lea a0, [a0]-0x8000
0000:808835D4 movh.a a1, #0xA081
0000:808835D8 lea a1, [a1]-0x8000
0000:808835DC movh.a a8, #0x8005
0000:808835E0 lea a8, [a8]-0x7800
0000:808835E4 movh.a a9, #0xD001
0000:808835E8 lea a9, [a9]-0x4000
</pre>

What that means, is that at any point in the code, these registers always have the following values:
<pre>
a0: 0xD0018000
a1: 0xA0808000
a8: 0x80048800
a9: 0xD000C000
</pre>

A quick example of how this is implemented in code:
<pre>
8019044a c9 00 de c9 ld.h d0,[a0]-0x60e2
</pre>

This takes the value of a0 (0xD0018000), subtracts 0x60e2 (=0xD0011F1E), and pulls the value of that memory address into d0. In the case of one common software version, that's:

<pre>
/begin MEASUREMENT tia_cha_up
"Air Temperature upstream the Charger"
SWORD
_CNV_A_R_CHRG_LINEA_171_CM
1
100.
-48.
335.994140625
DISPLAY_IDENTIFIER TIA_CHA_UP
ECU_ADDRESS 0xd0011f1e
FORMAT "%7.3"
/begin IF_DATA ETK
KP_BLOB
0xd0011f1e
INTERN
2
RASTER 30
/end IF_DATA
/end MEASUREMENT
</pre>

← Older revision		Revision as of 02:06, 4 December 2020
Line 60:		Line 60:
	/end MEASUREMENT		/end MEASUREMENT
	</pre>		</pre>
		+
		+	== Table address lookup ==
		+	Table lookup in the calibration isn't as straightforward.
		+	Occasionally you'll see reference in code to something like "0x8083DF8C". 0x8------- is the same as 0xA-------. So "0x8083DF8C" in the ASM is actually reference to 0xA083DF8C

← Older revision		Revision as of 17:04, 23 November 2020
Line 2:		Line 2:

	=Helpful links=		=Helpful links=
		+	https://www.infineon.com/dgdl/tc_v131_instructionset_v138.pdf?fileId=db3a304412b407950112b409b6dd0352
		+
	https://www.infineon.com/dgdl/Infineon-SAK-TC1796-256F150E%20BE-DS-v01_00-EN.pdf?fileId=5546d46249a28d750149a34e1f28045d		https://www.infineon.com/dgdl/Infineon-SAK-TC1796-256F150E%20BE-DS-v01_00-EN.pdf?fileId=5546d46249a28d750149a34e1f28045d

@@ Line 3: / Line 3: @@
 =Helpful links=
 https://www.infineon.com/dgdl/Infineon-SAK-TC1796-256F150E%20BE-DS-v01_00-EN.pdf?fileId=5546d46249a28d750149a34e1f28045d
 https://www.infineon.com/dgdl/TriCore_EABI_v2_3.pdf?fileId=db3a304412b407950112b40f8d7a142b
 =Quick Reference=

← Older revision		Revision as of 17:03, 23 November 2020
Line 1:		Line 1:
	= Purpose of this section =		= Purpose of this section =

−		+	=Helpful links=
		+	https://www.infineon.com/dgdl/Infineon-SAK-TC1796-256F150E%20BE-DS-v01_00-EN.pdf?fileId=5546d46249a28d750149a34e1f28045d
		+	https://www.infineon.com/dgdl/TriCore_EABI_v2_3.pdf?fileId=db3a304412b407950112b40f8d7a142b

@@ Line 29: / Line 29: @@
 a1:  0xA0808000
 a8:  0x80048800
 a9:  0xD000C000
 </pre>