Hello,
Taking inspiration from the Teensy 4.1 (and the NXP 1060-EVK) I've attempted to make my own custom board.
Unfortunately I've run into hardware issues and hoping to use the experience of the forum to resolve them and then happy to supply the parts of the MCU design if it can help others.
I recognise that parts of the design are outside the scope of teensy, but hope the experience with the same chip in teensy can help me.
My issues are:
- In "Internal Boot" I can flash the chip using SWD (MCUXpresso)
- In "Serial Downloader" the chip isn't accessible.
- When flashing the chip with a program to toggle an LED, the LED will toggle
- When flashing the chip with a program to output on UART "Hello World", there is no communication over UART (and a Hardfault when debugging)
Following the Hardware Design Guidelines my power up appears to fulfill the requirements and those listed by PJRC:
www.pjrc.com
I also have a switch to GND on the POR_B circuit, so I can GND POR_B during the entire power up and I still have the same issues.
All my voltages are stable and conform to the requirements in the Hardware Design Guideline:
(VDD_SOC_IN is nearing the upper limit, but could be lowered in the software)
I can also supply my board with an alternative 5V (USB not connected) but the issues are the same.
My 24MHz crystal also appears to fulfill the requirements. Below are measurement on the XTALO pin:
And here the crystals on the board:
UART is being pulled up to ensure no invalid triggers:
The BOOT_CFG pins are all being pulled to GND:
On/Off are pulled up:
I'd appreciate any and all help. I'm stumped...
Cheers,
Sam
Taking inspiration from the Teensy 4.1 (and the NXP 1060-EVK) I've attempted to make my own custom board.
Unfortunately I've run into hardware issues and hoping to use the experience of the forum to resolve them and then happy to supply the parts of the MCU design if it can help others.
I recognise that parts of the design are outside the scope of teensy, but hope the experience with the same chip in teensy can help me.
My issues are:
- In "Internal Boot" I can flash the chip using SWD (MCUXpresso)
- In "Serial Downloader" the chip isn't accessible.
- When flashing the chip with a program to toggle an LED, the LED will toggle
- When flashing the chip with a program to output on UART "Hello World", there is no communication over UART (and a Hardfault when debugging)
Following the Hardware Design Guidelines my power up appears to fulfill the requirements and those listed by PJRC:
PJRC Store
I also have a switch to GND on the POR_B circuit, so I can GND POR_B during the entire power up and I still have the same issues.
All my voltages are stable and conform to the requirements in the Hardware Design Guideline:
(VDD_SOC_IN is nearing the upper limit, but could be lowered in the software)
| USB_OTG_VBUS | 5.05 | ||
| 5V_Sys | 5.03 | ||
| SNVS | 3.3 | ||
| On / Wake Up | 3.28 | ||
| POR_B | 3.26 | ||
| 3.3V_DCDC / 3.3V_SYS | 3.29 | ||
| VDD_High_In | 3.29 | VDD_SOC_IN | 1.284 |
| VDD_SNVS_IN | 3.26 | VDD_HIGH_CAP | 2.53 |
| NVCC_GPIO | 3.3 | NVCC_PLL | 1.118 |
| VDDA_ADC_3P3 | 3.29 | VDD_USB_CAP | 2.42 (3.0) (EVK101x 2.64, EVK106x 3.23) |
| DCDC_IN | 3.29 | VDD_SNVS_CAP | 1.08 |
| NVCC_SD0 | 3.29 | ||
| NVCC_SD1 | 3.29 | ||
| NVCC_EMC | 3.3 | ||
| UART1_RX | 3.3 | ||
| UART1_TX | 3.29 |
I can also supply my board with an alternative 5V (USB not connected) but the issues are the same.
My 24MHz crystal also appears to fulfill the requirements. Below are measurement on the XTALO pin:
And here the crystals on the board:
UART is being pulled up to ensure no invalid triggers:
The BOOT_CFG pins are all being pulled to GND:
On/Off are pulled up:
I'd appreciate any and all help. I'm stumped...
Cheers,
Sam