MCUdude
commented
3 years ago Hi! I'm sorry, but this PR would most likely not get merged. Here's why:
- The idea with my Arduino cores is that they still should have a little bit of the Arduino spirit left; Don't "expose" features most user don't use/need anyways. In my opinion, CLKO is one of them. The same goes for various startup times and JTAG enable. It would just make the tools many longer and more overwhelming. Other popular cores such as ATTinyCore have everything exposed, but I've chosen to no go that path.
- But, MightyCore (and my other cores) are for "Advanced" as well. Features like JTAGEN and CLKO are supported through PlatformIO, which is IMO a much better tool for larger projects anyways. You can specify your fuse settings in platformio.ini, and the CLKO option will be enabled. It's very easy to do.
; Run the following command to set fuses
; pio run -e fuses_bootloader -t fuses
; Run the following command to set fuses + burn bootloader
; pio run -e fuses_bootloader -t bootloader
[env:fuses_bootloader]
board_hardware.oscillator = external ; Oscillator type
board_hardware.uart = uart0 ; Set UART to use for serial upload
board_bootloader.speed = 115200 ; Set bootloader baud rate
board_hardware.bod = 2.7v ; Set brown-out detection
board_hardware.eesave = yes ; Preserve EEPROM when uploading using programmer
board_hardware.ckout = yes ; Enable CLKO on pin PB1
upload_protocol = usbasp ; Use the USBasp as programmer
upload_flags = ; Select USB as upload port and divide the SPI clock by 8
-PUSB
-B8
DrItanium
I have been using the atmega1284p as a chipset to interface with an intel i960Sx processor. One of the features of AVR chips is the ability to output the MCU clock signal through the CLKO pin. This pull request adds this ability through the clock speed menu in the arduino IDE.
From the commit log:
Most AVR chips provide the ability to emit the processor's clock cycle on a specific GPIO (the name provided is CLKO). This is done by changing some of the fuses at bootloader programming time. The upside is that the same clock that powers the microcontroller can be provided to other devices in your project.
The downside is that you lose the use of the CLKO pin as a GPIO.
I have exposed this option as a different speed grade for 16 and 20 MHz for the 1284, 644, and 164 Atmega chips. This ability isn't bound to just 16 and 20MHz speeds but I have no need for the other speeds in my own projects.
I also only exposed this for the 1284, 644, and 164 because those are the chips I actually own and can easily test. I did not want to expose the option on chips that I myself do not own and cause a problem for someone else.