| // Copyright 2019 The Pigweed Authors |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); you may not |
| // use this file except in compliance with the License. You may obtain a copy of |
| // the License at |
| // |
| // https://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| // License for the specific language governing permissions and limitations under |
| // the License. |
| |
| #include <Arduino.h> |
| |
| #include <cinttypes> |
| #include <cstdint> |
| |
| #include "pw_preprocessor/compiler.h" |
| #include "pw_sys_io/sys_io.h" |
| |
| extern "C" void pw_sys_io_Init() { Serial.begin(115200); } |
| |
| namespace pw::sys_io { |
| |
| // Wait for a byte to read on USART1. This blocks until a byte is read. This is |
| // extremely inefficient as it requires the target to burn CPU cycles polling to |
| // see if a byte is ready yet. |
| |
| Status ReadByte(std::byte* dest) { |
| while (true) { |
| if (TryReadByte(dest).ok()) { |
| return OkStatus(); |
| } |
| } |
| } |
| |
| Status TryReadByte(std::byte* dest) { |
| if (!Serial.available()) { |
| return Status::Unavailable(); |
| } |
| *dest = static_cast<std::byte>(Serial.read()); |
| return OkStatus(); |
| } |
| |
| // Send a byte over the default Arduino Serial port. |
| Status WriteByte(std::byte b) { |
| // Serial.write() will block until data can be written. |
| Serial.write((uint8_t)b); |
| return OkStatus(); |
| } |
| |
| // Writes a string using pw::sys_io, and add newline characters at the end. |
| StatusWithSize WriteLine(const std::string_view& s) { |
| size_t chars_written = 0; |
| StatusWithSize result = WriteBytes(std::as_bytes(std::span(s))); |
| if (!result.ok()) { |
| return result; |
| } |
| chars_written += result.size(); |
| |
| // Write trailing newline. |
| result = WriteBytes(std::as_bytes(std::span("\r\n", 2))); |
| chars_written += result.size(); |
| |
| return StatusWithSize(result.status(), chars_written); |
| } |
| |
| } // namespace pw::sys_io |