This commit adds I2C timeouts for nrf51 and nrf52 (but not yet for
others like nrf52840).
Tested on the PineTime, where I now got a timeout instead of hanging and
resetting due to a watchdog reset.
* add gosched calls to UART
* add UART.flush() stubs for all supported architectures
* add comment un uart.go on flush functionality
* uart.writeByte as base of UART usage
* fix NXP having duplicate WriteByte
* fix writeByte not returning error on some platforms
* add flush method for fe310 device
* check for error in WriteByte call to writeByte
This adds FieldByNameFunc, which some libraries like reflect2 need.
For my usecase I could also just stub FieldByNameFunc to panic, but
figured that it would work OK to just make it work. I'm not sure if
the overhead to FieldByName using a closure is acceptable.
Signed-off-by: Tyler Rockwood <rockwood@redpanda.com>
Found while working on the PineTime. For some reason it still kind of
works in most cases, but I was hitting this issue when interacting with
two different I2C devices (the touch sensor and the BMA421).
The regular port access is around 4 cycles, instead of the usual 2
cycles for a store instruction on Cortex-M0+. The IOBUS however is
faster, I didn't measure exactly but I guess it's 2 cycles as expected.
This fixes a bug in the WS2812 driver that only happens on samd21 chips:
https://github.com/tinygo-org/drivers/issues/540
I didn't add this method in the initial PR.
Also, I found that a few of my assumptions were incorrect. I've changed
the code that configures the pin to make input (floating and pullup)
actually work. These chips really are quite different from all the older
AVRs.
This is just support for the chip, no boards are currently supported.
However, you can use this target on a custom board.
Notes:
- This required a new runtime and machine implementation, because the
hardware is actually very different (and much nicer than older
AVRs!).
- I had to update gen-device-avr to support this chip. This also
affects the generated output of other AVRs, but I checked all chips
we support and there shouldn't be any backwards incompatible
changes.
- I did not implement peripherals like UART, I2C, SPI, etc because I
don't need them. That is left to do in the future.
You can flash these chips with only a UART and a 1kOhm resistor, which
is really nice (no special hardware needed). Here is the program I've
used for this purpose: https://pypi.org/project/pymcuprog/
This basically reverts https://github.com/tinygo-org/tinygo/pull/3357
and replaces it with a different mechanism to get to the same goal.
I do not think filtering tags like this is a good idea: it's the wrong
part of the compiler to be concerned with such tags (that part sets
tags, but doesn't modify existing tags). Instead, I've written the
//go:build lines in such a way that it has the same effect: WASI
defaults to leveldb, everything else defaults to fnv, and it's possible
to override the default using build tags.
It could be expensive to call Size() three times, and it is unnecessary.
Instead, do it only once.
This results in a very small reduction of binary size if Zero() is used.
