LPC5536 SWD mode or ISP

[Bela1]

Ladies and Gentlemen,

reading different documentation, I got a bit confused.

I am drawing a new schema, with LPC5536JBD100 in there. My question is about the debug interface.

I've got MCUXpresso IDE 11.9.0_2144 as development environment and a recently purchased MCU-LINK-Pro as programmer board. My own HW is just in the schematic phase.

In the schematic of MCU-LINK-Pro, there's pin7 used as ISP-CTRL.

In the schema of LPCXpresso5536EVK there's J16 as SWD connector, but pin 7 connects to a jumper, it is not under uC control.

In the HW design guidelines AN13707, Debug and Programming Interface section, Figure 7, there's an example schema, with only 4 signals, no ISP-CTRL to PIO0_5. In the debug connector pinout, pin7 doesn't exist at all.

In AN13033, page 13, Figure 7 and figure 8 shows the same connection.

Which one is the right connection? I'd like to be able to download a new firmware through SWD, and also be able to debug it, maybe single-step too. In-System programming would be a "nice to have" feature, through USB or through I2C, when possible.

Currently, my schema pulls down PIO0_5 and PIO0_7 too, through 10k. Pio0_5 can be pulled high by an external signal.

[Pavel_Hernandez · Accepted solution]

Hello, my name is Pavel, and I will be supporting your case, I reviewed both app notes, and the connection is right, you can use it. The J16 has the jumper JP25 to put the MCU (LPC55s69) that acts as a debugger on the board in DFU (device firmware update) or in another way ISP to update the firmware or change the flavor of the firmware to P&E, Link Server, or J-Link, but remember this the EVK has all on it this has a debugger.

If you want to use your board hardware you will not need the debugger on the board, the MCU target LPC5536 to use the ISP you can find on the schematic as BOOT CONFIG to set.

Let me know if you have more doubts.

Best regards,
Pavel