LS1012A programming and debugging

[rahulsoni]

Hello NXP Team,

I'm designing a custom board based on LS1012A RDB design. In the reference design, NXP has used K22 kinetics MCU for debugging purpose. 

From the datasheet I can see that we have to use JTAG device to program the LS1012A device but in the reference design, K22 MCU is being used for programming. 

Can you please let me know what is the exact application of K22 MCU? Can I design my custom board without it and program the LS1012A using JTAG?

Does K22 give us an ability to program the LS1012 serially using USB cable? If not, then why this IC is included in the design?

Apart from programming, I want to confirm the debugging port for LS1012. The datasheet says that UART1 is the console port and we can take out UART lines for console prints and don't require K22 MCU. Please correct me if I'm wrong.

Thanks in advance. 

[ufedor]

K22 MCU can be used as a CMSIS DAP on the LS1012ARDB.

The CMSIS DAP provides low speed debug functionality for the LS1012A SoC.

You wrote:

> Can I design my custom board without it and program the LS1012A using JTAG?

Yes.

[rahulsoni]

Hello ufedor,

Thanks for your response.

"Does K22 give us an ability to program the LS1012 serially using USB cable? If not, then why this IC is included in the design?

Apart from programming, I want to confirm the debugging port for LS1012. The datasheet says that UART1 is the console port and we can take out UART lines for console prints and don't require K22 MCU. Please correct me if I'm wrong."

Can you please answer the above query?

[ufedor]

Initial board bring-up when it does not possess RCW is not possible by means of the CMSIS-DAP. Further programming tasks are possible.

> I want to confirm the debugging port for LS1012. The datasheet says that UART1 is

> the console port and we can take out UART lines for console prints and don't require K22 MCU

Correct.

[rahulsoni]

Hello Ufedor,

Hope you are doing good.

I was just checking the reference design and saw that for RS 232, NXP has used LTC2801 transceiver which is half duplex RS 232 transceiver.

My doubt is, with RS 232 half-duplex transceiver, will the user be able to see the console prints and send the inputs simultaneously? 

In general, we always go with full duplex RS 232 transceivers like MAX3232 etc. Why NXP used half duplex transceiver?

[ufedor]

> LTC2801 transceiver which is half duplex RS 232 transceiver.

This statement is not fully correct.

The LTC2081 has half-duplex mode (active when PS = logic high) - refer to the LTC2081 datasheet.

As you can see this is not the case for the LS1012ARDB.