SPRUIM2H May 2020 – October 2023 AM2431 , AM2432 , AM2434 , AM6411 , AM6412 , AM6421 , AM6422 , AM6441 , AM6442
The EMU1 and EMU0 device pins are used to convey debug boot mode behavior and can also be used as part of a boundary scan compliance sequence to enable boundary scan features.
Debug Boot Mode
EMU1 and EMU0 are sampled when MCU_PORz is de-asserted and the decoded value determines the debug boot mode behavior as detailed in Table 13-5.
Sample Time | EMU1 | EMU0 | Boot Mode | Behavior |
---|---|---|---|---|
MCU_PORz deassertion | 0 | 0 | Reserved | Reserved for future use |
0 | 1 | Reserved | Reserved for future use | |
1 | 0 | Wait-In-Reset (WIR) | Device will remain quiescent until a debug connection is established and the debugger releases WIR. This mode is useful for debugging boot sequences. | |
1 | 1 | Normal | Device boots normally. Debug can connect at any time but the context will be post-boot. |
Boundary Scan Compliance
EMU1 and EMU0 are sampled when TRSTz is de-asserted and the decoded value determines the debug boot mode behavior as detailed in Table 13-6.
Sample Time | EMU1 | EMU0 | Boundary Scan Compliance | Behavior |
---|---|---|---|---|
TRSTn deassertion | 0 | 1 | Boundary Scan Enabled | The device’s Boundary Scan TAP is connected to the device’s JTAG interface. |
0 | 0 | |||
1 | 0 | Boundary Scan Disabled | The device’s SWJ-DP is connected to the device’s JTAG interface. | |
1 | 1 |