MK20DX128VFM5 IC question

[shinezen]

i design circuit board , i use the MK20DX128VFM5  IC ,the power is ok

1.why  IC pin 19(reset pin) have clock 18khz?

2.the IC initial firmware is open sda2.1??

3.i have a SEGGER JLINK (JTAG),so can i use that progamming MK20DX128VFM5?

4.can i  programming MK20DX128VFM5 IC by usb port

thanks for your help

[rastislav_pavlanin]

Hi,

not clear what kind of board is used in your design. Is it our FRDM board? or your based design.

answers:

1. looks like your K20 device is in periodic reset e.g. caused by core lock up due to blank flash content.

2. well, if it is our FRDM board you use then OpenSDA K20 device contains OpenSDA bootloader application firmware pre-programmed. However, if it is K20 you have bought then the device is blank (empty flash content, all 0xFFFFFFFF).

3. yes, you can use jLink to program the device

4. ? if FRDM board used then you need to use SDA JTAG connector (10 pins 50mils micro header), we usually do not populate it on FRDM boards (you need to buy it and populate). You cannot use USB on FRDM board to program K20 OpenSDA device.

[Hui_Ma]

Hi

Could you let us know which board you are using? Thanks.

Wish it helps.

Have a great day,
Ma Hui
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