A boot mode buffer (SN74AVC8T245RHL) is used to isolate the boot mode controls that are driven through
either the DIP switch or the I2C IO expander. The test automation circuit is powered by an always on supply that
is generated from a dedicated regulator (TPS7A0533PDBVT).
The test automation header supports two I2C interfaces. Bootmode_I2C connects to the boot mode buffer to
control the bootmode of the AM243x while the other I2C interface is connected to the I2C1 port of the AM243x.
Table 4-16. Test Automation Header Pinout
Pin #
IO Direction
Signal
Description
1
Power
VCC3V3_TA
Power for test automation header
2
Power
VCC3V3_TA
3
Power
VCC3V3_TA
4
N/A
Reserved
5
N/A
Reserved
6
N/A
Reserved
7
Ground
DGND
8
N/A
Reserved
9
N/A
Reserved
10
N/A
Reserved
11
N/A
Reserved
12
N/A
Reserved
13
N/A
Reserved
14
N/A
Reserved
15
N/A
Reserved
16
Ground
DGND
17
N/A
Reserved
18
N/A
Reserved
19
N/A
Reserved
20
N/A
Reserved
21
N/A
Reserved
22
N/A
Reserved
23
N/A
Reserved
24
N/A
Reserved
25
Ground
DGND
26
Output
TEST_POWERDOWN
Used to power down the board
27
Output
TEST_PORZn
Used to reset the SoC PORz
28
Output
TEST_WARMRESETn
Used to reset the SoC Warm Reset
29
N/A
Reserved
30
Output
TA_SOC_INTn
Interrupt to SoC
31
Bidirectional
TEST_GPIO2
32
Output
TEST_GPIO3
Used to disable the BOOTMODE buffer
33
Outpu
TEST_GPIO4
Used to Reset the BOOTMODE IO Expander
34
Ground
DGND
35
N/A
Reserved
36
Bidirectional
SOC_I2C1_TA_SCL
Clock signal for SoC I2C
37
Bidirectional
BOOTMODE_I2C_SCL
Clock signal for I2C IO expander for boot mode
38
Bidirectional
SOC_I2C1_TA_SDA
Data signal for SoC I2C
39
Bidirectional
BOOTMODE_I2C_SDA
Data signal for I2C IO expander for boot mode
40
Ground
DGND
41
Ground
DGND
Hardware Description
SPRUJ12B – AUGUST 2021 – REVISED OCTOBER 2022
AM243x LaunchPad™ Development Kit User's Guide
45
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