Split into main/net/tusb_config, extract ring_buffer and usb_cdc headers

CMakeLists.txt

@@ -10,8 +10,9 @@ set(CMAKE_CXX_STANDARD 23)
 pico_sdk_init()
 
 add_executable(picomap
-	picomap.cpp
-	usb.cpp
+	main.cpp
+	net.cpp
+	tusb_config.cpp
 	w6300/w6300.cpp
 )
 

include/net.h

@@ -0,0 +1,3 @@
+#pragma once
+
+bool net_init();

include/ring_buffer.h

@@ -0,0 +1,44 @@
+#pragma once
+#include <array>
+#include <cstdint>
+#include <span>
+
+template <uint16_t N>
+struct ring_buffer {
+    std::array<uint8_t, N> data = {};
+    uint16_t head = 0;
+    uint16_t tail = 0;
+
+    uint16_t used() const { return tail - head; }
+    uint16_t free() const { return N - used(); }
+    bool empty() const { return head == tail; }
+
+    void push(std::span<const uint8_t> src) {
+        if (src.size() > free()) return;
+        for (auto b : src)
+            data[(tail++) % N] = b;
+    }
+
+    uint16_t peek(std::span<uint8_t> dst) const {
+        uint16_t len = dst.size() < used() ? dst.size() : used();
+        for (uint16_t i = 0; i < len; i++)
+            dst[i] = data[(head + i) % N];
+        return len;
+    }
+
+    void consume(uint16_t len) {
+        head += len;
+        if (head >= N) {
+            head -= N;
+            tail -= N;
+        }
+    }
+
+    std::span<const uint8_t> read_contiguous() const {
+        uint16_t offset = head % N;
+        uint16_t contig = N - offset;
+        uint16_t pending = used();
+        uint16_t len = pending < contig ? pending : contig;
+        return {data.data() + offset, len};
+    }
+};

include/usb_cdc.h

@@ -0,0 +1,31 @@
+#pragma once
+#include <cstdint>
+#include <span>
+#include <vector>
+#include "tusb.h"
+#include "ring_buffer.h"
+
+struct usb_cdc {
+    ring_buffer<512> tx;
+
+    void send(std::span<const uint8_t> data) {
+        tx.push(data);
+        drain();
+    }
+
+    void send(const std::vector<uint8_t>& data) {
+        send(std::span<const uint8_t>{data});
+    }
+
+    void drain() {
+        while (!tx.empty()) {
+            uint32_t avail = tud_cdc_write_available();
+            if (avail == 0) break;
+            auto chunk = tx.read_contiguous();
+            if (chunk.size() > avail) chunk = chunk.first(avail);
+            tud_cdc_write(chunk.data(), chunk.size());
+            tx.consume(chunk.size());
+        }
+        tud_cdc_write_flush();
+    }
+};

main.cpp

@@ -0,0 +1,59 @@
+#include "pico/stdlib.h"
+#include "pico/bootrom.h"
+#include "pico/unique_id.h"
+#include "tusb.h"
+#include "wire.h"
+#include "usb_cdc.h"
+#include "net.h"
+#include "w6300.h"
+
+static usb_cdc usb;
+
+int main() {
+    tusb_init();
+
+    net_init();
+
+    static static_vector<uint8_t, 256> rx_buf;
+
+    while (true) {
+        tud_task();
+
+        usb.drain();
+
+        while (tud_cdc_available()) {
+            uint8_t byte;
+            if (tud_cdc_read(&byte, 1) != 1) break;
+
+            rx_buf.push_back(byte);
+
+            auto msg = try_decode(rx_buf);
+            if (!msg) {
+                if (rx_buf.full()) rx_buf.clear();
+                continue;
+            }
+
+            rx_buf.clear();
+
+            switch (msg->type_id) {
+            case RequestPICOBOOT::ext_id:
+                usb.send(encode_response(msg->message_id, ResponsePICOBOOT{}));
+                sleep_ms(100);
+                reset_usb_boot(0, 1);
+                break;
+            case RequestInfo::ext_id: {
+                ResponseInfo resp;
+                pico_unique_board_id_t uid;
+                pico_get_unique_board_id(&uid);
+                std::copy(uid.id, uid.id + 8, resp.board_id.begin());
+                auto ninfo = w6300::get_net_info();
+                resp.mac = ninfo.mac;
+                usb.send(encode_response(msg->message_id, resp));
+                break;
+            }
+            }
+        }
+
+        __wfi();
+    }
+}

net.cpp

@@ -0,0 +1,24 @@
+#include "net.h"
+#include "pico/unique_id.h"
+#include "w6300.h"
+
+bool net_init() {
+    w6300::init_spi();
+    w6300::init_critical_section();
+    w6300::reset();
+    w6300::init();
+    if (!w6300::check()) return false;
+
+    pico_unique_board_id_t uid;
+    pico_get_unique_board_id(&uid);
+    w6300::net_info info = {};
+    info.mac[0] = (uid.id[0] & 0xFC) | 0x02;
+    info.mac[1] = uid.id[1];
+    info.mac[2] = uid.id[2];
+    info.mac[3] = uid.id[3];
+    info.mac[4] = uid.id[4];
+    info.mac[5] = uid.id[5];
+    w6300::init_net(info);
+
+    return true;
+}

picomap.cpp

@@ -1,120 +0,0 @@
-#include "pico/stdlib.h"
-#include "pico/bootrom.h"
-#include "pico/unique_id.h"
-#include "tusb.h"
-#include "wire.h"
-
-#include "w6300.h"
-
-struct tx_buf {
-    uint8_t data[512];
-    uint16_t head = 0;
-    uint16_t tail = 0;
-
-    uint16_t used() const { return tail - head; }
-    uint16_t free() const { return sizeof(data) - used(); }
-    bool empty() const { return head == tail; }
-
-    void push(const uint8_t* src, uint16_t len) {
-        if (len > free()) return;
-        for (uint16_t i = 0; i < len; i++)
-            data[(tail + i) % sizeof(data)] = src[i];
-        tail += len;
-    }
-
-    void drain() {
-        while (!empty()) {
-            uint32_t avail = tud_cdc_write_available();
-            if (avail == 0) break;
-            uint16_t offset = head % sizeof(data);
-            uint16_t contig = sizeof(data) - offset;
-            uint16_t pending = used();
-            uint16_t chunk = pending < contig ? pending : contig;
-            if (chunk > avail) chunk = avail;
-            tud_cdc_write(data + offset, chunk);
-            head += chunk;
-        }
-        tud_cdc_write_flush();
-        if (head >= sizeof(data)) {
-            head -= sizeof(data);
-            tail -= sizeof(data);
-        }
-    }
-};
-
-static tx_buf usb_tx;
-
-static void send_bytes(const std::vector<uint8_t>& data) {
-    usb_tx.push(data.data(), data.size());
-    usb_tx.drain();
-}
-
-static bool w6300_init() {
-    w6300::init_spi();
-    w6300::init_critical_section();
-    w6300::reset();
-    w6300::init();
-    if (!w6300::check()) return false;
-
-    pico_unique_board_id_t uid;
-    pico_get_unique_board_id(&uid);
-    w6300::net_info info = {};
-    info.mac[0] = (uid.id[0] & 0xFC) | 0x02;
-    info.mac[1] = uid.id[1];
-    info.mac[2] = uid.id[2];
-    info.mac[3] = uid.id[3];
-    info.mac[4] = uid.id[4];
-    info.mac[5] = uid.id[5];
-    w6300::init_net(info);
-
-    return true;
-}
-
-int main() {
-    tusb_init();
-
-    w6300_init();
-
-    static static_vector<uint8_t, 256> rx_buf;
-
-    while (true) {
-        tud_task();
-
-        usb_tx.drain();
-
-        while (tud_cdc_available()) {
-            uint8_t byte;
-            if (tud_cdc_read(&byte, 1) != 1) break;
-
-            rx_buf.push_back(byte);
-
-            auto msg = try_decode(rx_buf);
-            if (!msg) {
-                if (rx_buf.full()) rx_buf.clear();
-                continue;
-            }
-
-            rx_buf.clear();
-
-            switch (msg->type_id) {
-            case RequestPICOBOOT::ext_id:
-                send_bytes(encode_response(msg->message_id, ResponsePICOBOOT{}));
-                sleep_ms(100);
-                reset_usb_boot(0, 1);
-                break;
-            case RequestInfo::ext_id: {
-                ResponseInfo resp;
-                pico_unique_board_id_t uid;
-                pico_get_unique_board_id(&uid);
-                std::copy(uid.id, uid.id + 8, resp.board_id.begin());
-                auto ninfo = w6300::get_net_info();
-                resp.mac = ninfo.mac;
-                send_bytes(encode_response(msg->message_id, resp));
-                break;
-            }
-            }
-        }
-
-        __wfi();
-    }
-}