JTAG

This guide will show you how to use the JTAG interface on the phyCORE-i.MX8X development kit.

Requirement

J-LINK Segger Debugger
Download and Install the J-link software

Note

You can find more documentation about the J-link software here: https://wiki.segger.com/J-Link_Commander

Hardware Setup

Power off the development kit.
Connect your JTAG Debugger to X58 making sure the red line on the ribbon cable aligns with pin 1 on the header.
Power on the development kit and boot into Linux

Device Connection Setup

Open the J-link software and make sure your debugger is recognized.

J-Link Commander Console (Host)

SEGGER J-Link Commander V6.98a (Compiled Mar  5 2021 17:02:18)
DLL version V6.98a, compiled Mar  5 2021 17:01:02

Connecting to J-Link via USB...O.K.
Firmware: J-Link V11 compiled Jul 17 2020 16:24:07
Hardware version: V11.00
S/N: 51009799
License(s): GDB
VTref=0.000V


Type "connect" to establish a target connection, '?' for help
J-Link>

Initiate the connection sequence.

J-Link Commander Console (Host)

connect
Please specify device / core. <Default>: MK64FN1M0XXX12
Type '?' for selection dialog
Device>MK64FN1M0XXX12
Please specify target interface:
J) JTAG (Default)
S) SWD
T) cJTAG
TIF>J

Expected Output (Host)

Please specify device / core. <Default>: MK64FN1M0XXX12
Type '?' for selection dialog
Device>

Specify the device you are connecting to (MK64FN1M0XXX12)
J-Link Commander Console (Host)
```
MK64FN1M0XXX12
```
Expected Output (Host)
```
Please specify target interface:
J) JTAG (Default)
S) SWD
T) cJTAG
TIF>
```

Choose the target interface

J-Link Commander Console (Host)

Expected Output (Host)

Device position in JTAG chain (IRPre,DRPre) <Default>: -1,-1 => Auto-detect
JTAGConf>

Use the default “Device position” from above by hitting “Enter” to move to the next step.
Expected Output (Host)
```
Specify target interface speed [kHz]. <Default>: 4000 kHz
Speed>
```

Type in a device speed and hit “Enter”.

J-Link Commander Console (Host)

Expected Output (Host)

Device "MK64FN1M0XXX12" selected.


Connecting to target via JTAG
InitTarget()
Timeout while halting CPU.
TotalIRLen = 4, IRPrint = 0x01
JTAG chain detection found 1 devices:
#0 Id: 0x2890201D, IRLen: 04, JTAG-DP
DPv0 detected
Scanning AP map to find all available APs
AP[7]: Stopped AP scan as end of AP map has been reached
AP[0]: AXI-AP (IDR: 0x44770004)
AP[1]: AHB-AP (IDR: 0x24770011)
AP[2]: AHB-AP (IDR: 0x24770011)
AP[3]: AHB-AP (IDR: 0x84770001)
AP[4]: APB-AP (IDR: 0x54770002)
AP[5]: AHB-AP (IDR: 0x84770001)
AP[6]: AHB-AP (IDR: 0x84770001)
Iterating through AP map to find AHB-AP to use
AP[0]: Skipped. Not an AHB-AP
AP[1]: Core found
AP[1]: AHB-AP ROM base: 0xE00FF000
CPUID register: 0x410FC241. Implementer code: 0x41 (ARM)
Found Cortex-M4 r0p1, Little endian.
FPUnit: 6 code (BP) slots and 2 literal slots
CoreSight components:
ROMTbl[0] @ E00FF000
ROMTbl[0][0]: E000E000, CID: B105E00D, PID: 000BB00C SCS-M7
ROMTbl[0][1]: E0001000, CID: B105E00D, PID: 003BB002 DWT
ROMTbl[0][2]: E0002000, CID: B105E00D, PID: 002BB003 FPB
ROMTbl[0][3]: E0000000, CID: B105E00D, PID: 003BB001 ITM
ROMTbl[0][5]: E0041000, CID: B105900D, PID: 000BB925 ETM
ROMTbl[0][7]: E0043000, CID: B105900D, PID: 001BB908 CSTF
Cortex-M4 identified.
J-Link>

Connection Test

Type in “h” and hit “Enter” to halt the CPU core.

J-Link Commander Console (Host)

Expected Output (Host)

 PC = 1FFEBE76, CycleCnt = 00916A51
 R0 = 00000000, R1 = 000C0000, R2 = 00300000, R3 = 00180000
 R4 = 2001F76F, R5 = 41220000, R6 = 00C000C0, R7 = 2001F76F
 R8 = 2001F770, R9 = 0000051A, R10= 00008C01, R11= 001FC231
 R12= 20009419
 SP(R13)= 2001F730, MSP= 2001F730, PSP= 00000000, R14(LR) = 1FFEBE07
 XPSR = 61000000: APSR = nZCvq, EPSR = 01000000, IPSR = 000 (NoException)
 CFBP = 04000000, CONTROL = 04, FAULTMASK = 00, BASEPRI = 00, PRIMASK = 00

 FPS0 = 00000000, FPS1 = 00000000, FPS2 = 00000000, FPS3 = 00000000
 FPS4 = 00000000, FPS5 = 00000000, FPS6 = 00000000, FPS7 = 00000000
 FPS8 = 00000000, FPS9 = 00000000, FPS10= 00000000, FPS11= 00000000
 FPS12= 00000000, FPS13= 00000000, FPS14= 5C0100C4, FPS15= 00000004
 FPS16= 00000000, FPS17= 00000000, FPS18= 00000000, FPS19= 00000000
 FPS20= 00000000, FPS21= 00000000, FPS22= 00000000, FPS23= 00000000
 FPS24= 00000000, FPS25= 00000000, FPS26= 00000000, FPS27= 00000000
 FPS28= 00000000, FPS29= 00000000, FPS30= 00000000, FPS31= 00000000
 FPSCR= 00000000
 J-Link>

Type in “g” and hit “Enter” to start the CPU core. No output expected.
J-Link Commander Console (Host)
```
g
```
Type in “mem 0,0” and hit “Enter” to test memory read functionality. No output expected.
J-Link Commander Console (Host)
```
mem 0,0
```
Type in “mem 0,1” and hit “Enter” to test memory read functionality.
J-Link Commander Console (Host)
mem 0,1
Expected Output (Host)
```
00000000 = 00
```
Type in “mem 0,10” and hit “Enter” to test memory read functionality.
J-Link Commander Console (Host)
```
mem 0,10
```
Expected Output (Host)
```
00000000 = 00 FC 01 20 D1 06 00 00  7D 06 00 00 7D 06 00 00  ... ....}...}...
```

Exit the Software

J-Link Commander Console (Host)
exit