Overhaul flow control, logging, and build

.gitignore

@@ -33,3 +33,5 @@
 *.su
 
 serial
+
+build-*

Makefile

@@ -1,7 +1,7 @@
 CFLAGS += -std=c11 -g
 
 all: serial arduino
-serial: serial.c
+serial: serial.c config.h
 
 .PHONY: arduino upload clean clean-arduino
 

config.h

@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2017 Rodger Combs
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#define RATE 57600
+#define BRATE B57600
+
+#define HEADER_SIZE 0x400
+
+#define INPUT_SIZE 4
+#define INPUT_BATCH 8
+
+#define BUF_COUNT 0x80
+#define MS_TIMEOUT 10
+
+#define START_BYTE 0xFF
+#define FINISH_BYTE 0xFE
+
+#define REQ_BYTE 0x00
+#define ACK_BYTE 0x01

serial-n64/Makefile

@@ -0,0 +1,3 @@
+CXXFLAGS += -O3
+
+include ../arduino-mk/Arduino.mk

serial-n64/serial-n64.ino

@@ -61,6 +61,13 @@ void writeString(const char *string)
     writeByte(*string++);
 }
 
+void writeInt(int i, int radix)
+{
+  char localBuf[32];
+  itoa(i, localBuf, radix);
+  writeString(localBuf);
+}
+
 void writeLine(const char *line)
 {
   writeString(line);
@@ -83,7 +90,7 @@ byte readByte()
 
 void setup()
 {
-  Serial.begin(115200);
+  Serial.begin(RATE);
 
   noInterrupts();
 
@@ -233,18 +240,22 @@ inner_loop:
 }
 
 const char* sendMsg = NULL;
+int pendingAcks = 0;
 
 static void readSerial(bool timeout)
 {
   int ms = millis();
   int currentMs = ms;
   digitalWrite(13, HIGH);
-  if (sendMsg) {
-    writeLine(sendMsg);
-    sendMsg = NULL;
-  }
   while (buf->numElements(buf) <= (BUF_COUNT - INPUT_BATCH) && (!timeout || ((currentMs < ms + MS_TIMEOUT)) || buf->isEmpty(buf)))
   {
+    if (sendMsg) {
+      writeLine(sendMsg);
+      sendMsg = NULL;
+    }
+    for (int i = 0; i < pendingAcks; i++)
+      writeByte(ACK_BYTE);
+    pendingAcks = 0;
     int cmd;
     writeByte(REQ_BYTE);
     while ((cmd = readByteNow()) < 0x80) {
@@ -253,20 +264,22 @@ static void readSerial(bool timeout)
     }
     if (cmd == START_BYTE) {
       for (int i = 0; i < INPUT_BATCH && (!timeout || ((currentMs < ms + MS_TIMEOUT) && N64_QUERY)); i++) {
-        char localBuf[INPUT_SIZE + 2] = {0};
-        for (int j = 0; j < INPUT_SIZE + 1; j++) {
+        byte localBuf[INPUT_SIZE + 2] = {0};
+        for (int j = 0; j < (INPUT_SIZE * 8 + 8 + 6) / 7; j++) {
           int byte;
           while ((byte = readByteNow()) == -1) {
             if (timeout && !N64_QUERY)
               goto skip;
           }
-          localBuf[(j * 7) / 8]       |= byte >> (8 - (j % 7));
-          localBuf[((j * 7) + 7) / 8]  = byte << ((j % 7) + 1);
+          localBuf[(j * 7) / 8]      |= byte >> (7 - (j % 7));
+          localBuf[((j * 7) + 7) / 8] = byte << ((j % 7) + 1);
         }
-        if ((localBuf[0] ^ localBuf[1] ^ localBuf[2] ^ localBuf[3]) != localBuf[4])
+        if ((localBuf[0] ^ localBuf[1] ^ localBuf[2] ^ localBuf[3]) != localBuf[4]) {
           sendMsg = "Check failed!";
+          break;
+        }
         buf->add(buf, localBuf);
-        writeByte(ACK_BYTE);
+        pendingAcks++;
         currentMs = millis();
       }
     } else if (cmd == FINISH_BYTE) {
@@ -399,7 +412,9 @@ void loop()
             break;
 
         default:
-            writeLine("Unknown command!");
+            writeString("Unknown command: ");
+            writeInt(n64_command, 16);
+            writeByte('\n');
             break;
 
     }

serial.c

@@ -45,11 +45,11 @@ void write_7bit(int fd, const char *in, int len)
   unsigned char check = 0;
   for (int i = 0; i < len; i++) {
     out[(i * 8) / 7]    |=  in[i] >> 1 + (i % 7);
-    out[(i * 8) / 7 + 1] = (in[i] << 7 - (i % 7)) & 0x7F;
+    out[(i * 8) / 7 + 1] = (in[i] << 6 - (i % 7)) & 0x7F;
     check ^= in[i];
   }
   out[(len * 8) / 7]    |=  check >> 1 + (len % 7);
-  out[(len * 8) / 7 + 1] = (check << 7 - (len % 7)) & 0x7F;
+  out[(len * 8) / 7 + 1] = (check << 6 - (len % 7)) & 0x7F;
   write(fd, out, ((len + 1) * 8 + 6) / 7);
 }
 
@@ -75,7 +75,7 @@ int main(int argc, const char** argv)
 
   printf("Total size: %i\n", size);
 
-  speed_t baud = B115200;
+  speed_t baud = BRATE;
 
   struct termios settings;
   tcgetattr(outfd, &settings);