Hi All,
For my custom board, it has a LPC54S018JET180E and a NOR SPI External Flash. I would like to upload firmware to the NOR SPI External Flash from a PC. And I want the custom board to boot from the NOR SPI External Flash.
I want to use the "mcu link debug probe" for the programming, but I am unsure how to connect the "mcu link debug probe" to my custom board. Attached image is the interface I have so far. Or please suggest another programmer that can perform programming to the LPC540XX and the NOR SPI External Flash.
Thanks,
4/15/2025
Hi @mtsang
" I am unsure how to connect the "mcu link debug probe" to my custom board. "
Connecting MCU-Link to Your Board . You can use the JTAG (P2) connector you showed in your schematic.
And you want to boot from external flash.
I think you can refer to the hello world qspi xip demo.
BR
Harry
Hi Harry,
Thanks for your quick response!
I should connect my custom board's P2 to the J6 of the "MCU-Link", is that correct?
Also do I need to use pull-up resistor for all of the Jtag signals?
And where should "ISP-EN" to connect to?
Thanks,
4/16/2025
Hi @mtsang
Yes, according pio0_4 you need to add a SWITCH that pulls to GND during the programming .
tie the "ISP_EN" to the "P2_JTAG_TMS"?
No
BR
Harry
Hi Harry,
Thanks for the pio0_4 and ISP download details, will take note on that.
Do I need to add pull up/down resistors(what values) to my JTAG_(TCK/DO/DI/TRST/RESET#) signals?
Also I am still confused about where should I connect MCU-Link Pro's J7_ISP_EN (I decided to use MCU-Link Pro) to my custom board.
From the evk board schematic, I see "ISP_CTRL" drives the "IF_ISPEN" and "IF_ISPEN" connect to "PIO0_4" with a 0Ohm resistors. Since "pio0_4" for my schematic will be pulled down to the GND, does that mean I should leave the MCU-Link Pro's J7_ISP_EN open?
Thanks,
4/22/2025
Hi @mtsang
"Do I need to add pull up/down resistors(what values) to my JTAG_(TCK/DO/DI/TRST/RESET#) signals?"
I think you can refer to it.
Or you can also refer to this.
This schematic is a debuger for MCX, but they are similar.
"From the evk board schematic, I see "ISP_CTRL" drives the "IF_ISPEN" and "IF_ISPEN" connect to "PIO0_4" with a 0Ohm resistors. Since "pio0_4" for my schematic will be pulled down to the GND, does that mean I should leave the MCU-Link Pro's J7_ISP_EN open?"
Sorry, i don't know why MCU-Link Pro need to connect to the J7_ISP_EN?
BR
Harry
Hi Harry,
Thanks for the reference for the pull up/down resistors!
"Sorry, i don't know why MCU-Link Pro need to connect to the J7_ISP_EN?"
The "J7_ISP_EN" is from the MCU-Link Pro. And I am unsure where should the signal "ISP_EN" connect to the LPC540XX. Below pic is my JTAG port on my custom board. I am wondering where MCU-Link Pro's "J7_ISP_EN" suppose to connect to my custom board. My intention is to connect MCU-Link Pro's J7 connector to my custom board's P2.
Thanks,
4/24/2025
Hi @mtsang
I understand your intention, you are right.
You need select one pin in P2 to connect to the PIO0_5-ISP_EN-LED_SWD_ACT.
This is for the mcu link firmware update.
If enter mcu link pro isp mode.
You should communicate with is using USB mode.
This is the schematic diagram of MCU Link Pro.
I think this will be helpful to you.
BR
Harry
Hi Harry,
I just got the MCU-LINK PRO. Currently I am using MCU-LINK PRO as a J-Link Probe.
When I try to use the ""J-Link Commander" to connect with the target device(my custom board's LPC54S018JET180E) to verify the JTAG connection, it will pops up an error message "Could not measure total IR len. TDO is constant high."(Please see Pic1).
I used 10k pull up resistors for TMS, TDO, TDI, and 10k pull down resistor on TCK. I checked with an o-scope and I found TDO stills logic high and doesnt output any pulse/signal.
I also see that in the "Target Device Settings" from the J-Link Commander, it has three options of "LPC540XX", I suppose the "JXM" means chip's internal flash. But my device is "LPC54S018JET180E", so it should not have an internal flash. Which one should I choose and does it affect the JTAG connection.
Can you please provide advice on how to set up the MCU-LINK PRO/Custom Board properly?
Pic1
Pic2
Thanks,
5/27/2025
