Fix readme image

Modified the write with a hardcoded delay to avoid ack on every write.

.gitignore

@@ -163,3 +163,9 @@ tags
 [._]*.un~
 
 # End of https://www.toptal.com/developers/gitignore/api/vim,python
+
+# Binary files
+*.bin
+
+# Mac
+/**/.DS_Store

.vim/coc-settings.json

@@ -0,0 +1,6 @@
+{
+  "python.linting.pylintEnabled": true,
+  "python.linting.mypyEnabled": false,
+  "python.linting.enabled": true,
+  "python.formatting.provider": "black"
+}

README.md

@@ -1,4 +1,7 @@
 # eeprom_programmer
 A very basic EEPROM programmer, compatible with chips with up to 15 address lines.
 
+# Protoboard assembly
+![Protoboard assembly](images/protoboard_assembly.JPG)
+
 ##### This project was inspired by and based on [Ben Eater's programmer](https://github.com/beneater/eeprom-programmer)

arduino_programs/arduino_programmer/arduino_programmer.ino

@@ -17,8 +17,70 @@
 // Digital pins 8 to 13 correspond to PB0 to PB5
 
 byte lastOp;
+int lastAddressWritten;
+byte lastDataWritten;
+bool isFirstWrite = true;
+
 static char printBuff[128];
 
+void program();
+void dump(); 
+void erase();
+
+void dumpFirts256Bytes() {
+  byte data;
+  Serial.println("Reading EEPROM");
+  for (int addr = 0; addr < 256; addr += 16) {
+    sprintf(printBuff, "%04x:", addr);
+    Serial.print(printBuff);
+    for (int offset = 0; offset < 16; offset++) {
+      sprintf(printBuff, " %02x", readEEPROM(addr + offset)); 
+      Serial.print(printBuff);
+    }
+    Serial.println();
+  }
+}
+
+void setup() {
+  // put your setup code here, to run once:
+  pinMode(SHIFT_DATA, OUTPUT);
+  pinMode(SHIFT_CLK, OUTPUT);
+  pinMode(SHIFT_LATCH, OUTPUT);
+
+  digitalWrite(EEPROM_WE, HIGH);
+  pinMode(EEPROM_WE, OUTPUT);
+  
+  // Setting an invalid value.
+  lastOp = -1;
+
+  Serial.begin(115200);
+}
+
+void loop() {
+  static byte command;
+  // The loop function only process commands.
+  while (Serial.available() == 0);
+
+  command = Serial.read();
+
+  switch(command) {
+    case 0x00:
+    // Program the eeprom.
+      program();      
+    break;
+    case 0x01:
+    // Dump the eeprom.
+      dump();
+    break;
+    case 0x02:
+    // Erase the EEPROM (fill with 0xFF).
+      erase();
+    default:
+    // Ignore invalid commands.
+    break;
+  }
+}
+
 void latchOutput() {
   static byte latchMask = 0b00010000;
 
@@ -27,6 +89,7 @@ void latchOutput() {
   PORTD |= latchMask;
   delayMicroseconds(1);
   PORTD  &= ~latchMask;
+  delayMicroseconds(1);
 }
 
 void commitWrite() {
@@ -87,29 +150,43 @@ void setAddress(int address, bool outputEnable) {
   latchOutput();
 }
 
-byte readEEPROM(int address) {
-  // TODO: Think about adding a delay if the last operation was a write and where it is appropriate to put it.
-  // If the last operation wasn't a read we need to set our pins as input.
-  if (lastOp != LAST_OP_READ) {
-    setBusMode(READ_MODE);
-  }
-
+byte readBus(int address) {
   // In contrast with the write function, it's okay to set output enable after setting the
   // pins as inputs. This way, the arduino pins are already ready to sink current when the
   // EEPROM starts driving the bus.
-  byte result = (PINB << 3) | (PIND >> 5) ;
-
-  lastOp = LAST_OP_READ;
-  return result;
+  setAddress(address, true);
+  // For some reason, PINB takes a long time to update, a delay of a minimum of 2 microsends
+  // Must be added. The datasheet of the AT28C256 specifies a time from address to output of 150ns max
+  // and a time from output enabled to output of 70ns max, thus it makes no sense to wait 2000ns, but
+  // if it is not done, the most significant nibble is always 0xF.
+  delayMicroseconds(2);
+  return (PINB << 3) | (PIND >> 5);
 }
 
+byte readEEPROM(int address) {
+  // If the last operation wasn't a read we need to set our pins as input
+  if (lastOp != LAST_OP_READ) {
+    setBusMode(READ_MODE);
+    // If last op was a write we need to poll for valid data.
+    if (lastOp == LAST_OP_WRITE) {
+      while (readBus(lastAddressWritten) != lastDataWritten);
+    }
+  }
+  
+  lastOp = LAST_OP_READ;
+  return readBus(address);
+}
+
+void writeEEPROM(int address, byte data, bool pollOnPageChange) {
+  // Since we're performing page writes, we must poll the data when we change page.
+  if (
+    ((address & 0xFFC0) != (lastAddressWritten & 0xFFC0))
+    && isFirstWrite == false
+    && pollOnPageChange
+  ) {
+    while(readEEPROM(lastAddressWritten) != lastDataWritten);
+  }
   
-/**
- * Writes a single byte of data to the specified address.
- * If cooldown is true, the function adds a delay to avoid
- * reading incorrect data after a write.
- */
-void writeEEPROM(int address, byte data, bool cooldown) {
   // For the write case, must turn output enable off before setting the pins as outputs.
   // If we don't do this, for a brief period of time, both the arduino and the EEPROM would
   // drive the bus and this could case problems.
@@ -122,37 +199,71 @@ void writeEEPROM(int address, byte data, bool cooldown) {
   
   // EEPROM_D0 to D2 correspond to PD5 to PD7
   // EEPROM_D3 to D7 correspond to PB0 to PB4
-  PORTD &= (data << 5) & 0b00011111;
-  PORTB &= (data >> 3) & 0b11100000;
+  PORTD = (PORTD & 0b00011111 ) | (data << 5);
+  PORTB = (PORTB & 0b11100000) | (data >> 3) ;
+
+  // Slow version.
+  //for (int pin = EEPROM_D0; pin < EEPROM_D7; pin++, data >>= 1) {
+  //  digitalWrite(pin, data & 1);
+  //}
   
   commitWrite();
   lastOp = LAST_OP_WRITE;
+  isFirstWrite = false;
 
-  if (cooldown) {
-    delay(10);
+  lastAddressWritten = address;
+  lastDataWritten = data;
+}
+
+
+void disableSoftwareProtection() {
+
+  writeEEPROM(0x5555, 0xAA, false);
+  writeEEPROM(0x2AAA, 0x55, false);
+  writeEEPROM(0x5555, 0x80, false);
+  writeEEPROM(0x5555, 0xAA, false);
+  writeEEPROM(0x2AAA, 0x55, false);
+  writeEEPROM(0x5555, 0x20, false);
+
+  delay(10);
+}
+
+void erase() {
+  for (long addr = 0; addr < 32768; addr++) {
+    writeEEPROM(addr, 0xFF, true);
+  }
+  // Ack the operation.
+  Serial.write(0xFF);
+}
+
+void program() {
+  // For now, the programmer will always write to the whole eeprom.
+  byte value;
+  // The program will write byte by byte.
+  for (long addr = 0; addr < 32768; addr++) {
+    // Wait for next value.
+    while(Serial.available() == 0);
+    value = Serial.read();
+    writeEEPROM(addr, value, true);
   }
 }
 
+void dump() {
+  unsigned long startAddress = 0;
+  unsigned long byteCount = 0;
+  byte value;
+  // Wait and read the starting address to dump.
+  while (Serial.available() < 2);
+  startAddress |= Serial.read();
+  startAddress |= Serial.read() << 8;
 
-void setup() {
-  // put your setup code here, to run once:
-  pinMode(SHIFT_DATA, OUTPUT);
-  pinMode(SHIFT_CLK, OUTPUT);
-  pinMode(SHIFT_LATCH, OUTPUT);
-
-  digitalWrite(EEPROM_WE, HIGH);
-  pinMode(EEPROM_WE, OUTPUT);
-  
-  // Setting an invalid value.
-  lastOp = -1;
-
-  Serial.begin(9600);
-  
-  writeEEPROM(0x1234, 0x55, true);
-  writeEEPROM(0x4321, 0x7E, true);
-}
-
-void loop() {
-  // put your main code here, to run repeatedly:
+  // Wait and read the byte count.
+  while (Serial.available() < 2);
+  byteCount |= Serial.read();
+  byteCount |= Serial.read() << 8;
 
+  for (int address = startAddress; address < startAddress + byteCount; address++ ) {
+    value = readEEPROM(address);
+    Serial.write(value);
+  }
 }

arduino_programs/arduino_tester/arduino_tester.ino

@@ -10,8 +10,23 @@
 #define ADDRESS_CLOCK 18
 #define WRITE_CLOCK 19
 
+/*
+
+   PORT mappings for data pins:
+
+    2   PORTE 4
+    3   PORTE 5
+    4   PORTG 5
+    5   PORTE 3
+    6   PORTH 3
+    7   PORTH 4
+    8   PORTH 5
+    9   PORTH 6
+
+*/
+
 void setup() {
-  Serial.begin(9600);
+  Serial.begin(115200);
   attachInterrupt(digitalPinToInterrupt(ADDRESS_CLOCK), onAddressClock, RISING);
   attachInterrupt(digitalPinToInterrupt(WRITE_CLOCK), onWriteClock, FALLING);
 }
@@ -28,9 +43,15 @@ void onAddressClock() {
 
 void onWriteClock() {
   Serial.print("Data: 0b");
-  for (int pin = DATA_7; pin >= DATA_0; pin--) {
-    Serial.print(digitalRead(pin));
-  }
+  // TODO: Find a way of making this more readable.
+  Serial.print((PINH & 0x40) >> 6);
+  Serial.print((PINH & 0x20) >> 5);
+  Serial.print((PINH & 0x10) >> 4);
+  Serial.print((PINH & 0x08) >> 3);
+  Serial.print((PINE & 0x08) >> 3);
+  Serial.print((PING & 0x20) >> 5);
+  Serial.print((PINE & 0x20) >> 5);
+  Serial.print((PINE & 0x10) >> 4);
   Serial.println();
 }
 

cli/cli.py

@@ -0,0 +1,160 @@
+import argparse
+import time
+import serial
+from tqdm import tqdm
+
+
+def get_parsed_args():
+
+    parser = argparse.ArgumentParser()
+    subparsers = parser.add_subparsers(title="Operation to perform", dest="operation")
+
+    program_parser = subparsers.add_parser("program")
+    dump_parser = subparsers.add_parser("dump")
+    erase_parser = subparsers.add_parser("erase")
+
+    # Parser for the "program" subcommand.
+    program_parser.add_argument(
+        "-f",
+        "--file",
+        help="Binary file containing the program",
+        type=argparse.FileType("rb"),
+        required=True,
+    )
+
+    program_parser.add_argument(
+        "-p", "--port", help="Serial port where programmer is located", required=True
+    )
+
+    # Parser for the dump subcommand.
+    dump_parser.add_argument(
+        "-f",
+        "--file",
+        help="The file where the binary dump will be stored",
+        type=argparse.FileType("wb"),
+        required=True,
+    )
+
+    dump_parser.add_argument(
+        "-p", "--port", help="Serial port where programmer is located", required=True
+    )
+
+    dump_parser.add_argument(
+        "-s",
+        "--start",
+        help="The address where to start dumping",
+        type=int,
+        required=True,
+    )
+
+    dump_parser.add_argument(
+        "-c",
+        "--byte-count",
+        help="The amount of bytes to dump",
+        type=int,
+        required=True,
+    )
+
+    dump_parser.add_argument(
+        "--display",
+        help="Print the dump to the screen after storing it to the file",
+        action="store_true",
+    )
+
+    # Parser for the erase command .
+    erase_parser.add_argument(
+        "-p",
+        "--port",
+        help="Serial port where the programmer is located",
+        required=True,
+    )
+
+    return parser.parse_args()
+
+
+def program(args):
+    print("Programming...")
+    with serial.Serial(args.port, 115200) as ser:
+        # Give a chance to the arduino to reset.
+        # TODO: Arduino resets by default when opening a serial
+        # connection, there's ways to avoid this. Investigate more.
+        time.sleep(2)
+
+        # Sending command
+        ser.write((0).to_bytes(1, "big"))
+
+        bytes_to_write = args.file.read()
+        # Forward the bytes from the selected file
+        for i in tqdm(range(32 * 1024)):
+            value = (bytes_to_write[i]).to_bytes(1, "big")
+            ser.write(value)
+            # This delay was found by experimentation.
+            # A byte write in the arduino takes about 80us.
+            # Every 64 bytes (a page) we do data polling and could
+            # take much longer. A byte send given a 115200 baud rate
+            # should take ~70us, a 100us delay should give the EEPROM enough time
+            # to internally write the page withouh the UART read buffer (64 bytes)
+            # overflowing.
+            time.sleep(100.0 * 1e-6)
+        print("Done programming!")
+
+
+def dump(args):
+    print("Dumping...")
+    with serial.Serial(args.port, 115200) as ser:
+        address = int(args.start)
+        byte_count = int(args.byte_count)
+
+        # TODO: Avoid arduino autoreset.
+        print("Waiting for the arduino to reset...")
+        time.sleep(2)
+
+        # Sending command
+        ser.write((1).to_bytes(1, "big"))
+
+        # Sending address, low byte first.
+        ser.write((address & 0xFF).to_bytes(1, "big"))
+        ser.write(((address & 0xFF00) >> 8).to_bytes(1, "big"))
+        # Sending byte count, low byte first.
+        ser.write((byte_count & 0xFF).to_bytes(1, "big"))
+        ser.write(((byte_count & 0xFF00) >> 8).to_bytes(1, "big"))
+
+        # Read the stream coming from the Arduino and forward them
+        # to the user-selected dump file.
+        for _ in range(byte_count):
+            args.file.write(ser.read())
+        print("Done dumping!")
+
+
+def erase(args):
+    print("Erasing...")
+    with serial.Serial(args.port, 115200) as ser:
+
+        # TODO: Avoid arduino autoreset.
+        print("Waiting for the arduino to reset...")
+        time.sleep(2)
+
+        ser.write((2).to_bytes(1, "big"))
+
+        # Wait for the ack.
+        if ser.read() == b"\xFF":
+            print("Erasing completed!")
+        else:
+            print("Erasing failed")
+
+
+def main():
+    args = get_parsed_args()
+
+    if args.operation == "program":
+        program(args)
+    elif args.operation == "dump":
+        dump(args)
+    elif args.operation == "erase":
+        erase(args)
+    else:
+        print("Unrecognized command, exiting now...")
+
+
+if __name__ == "__main__":
+    main()

cli/requirements.txt

@@ -0,0 +1,17 @@
+appdirs==1.4.4
+astroid==2.4.2
+isort==5.6.4
+jedi==0.17.2
+lazy-object-proxy==1.4.3
+mccabe==0.6.1
+mypy-extensions==0.4.3
+parso==0.7.1
+pathspec==0.8.1
+pylint==2.6.0
+pyserial==3.5
+rope==0.18.0
+six==1.15.0
+toml==0.10.2
+tqdm==4.54.1
+typing-extensions==3.7.4.3
+wrapt==1.12.1

serial_monitor/requirements.txt

@@ -0,0 +1,16 @@
+appdirs==1.4.4
+astroid==2.4.2
+isort==5.6.4
+jedi==0.17.2
+lazy-object-proxy==1.4.3
+mccabe==0.6.1
+mypy-extensions==0.4.3
+parso==0.7.1
+pathspec==0.8.1
+pylint==2.6.0
+pyserial==3.5
+rope==0.18.0
+six==1.15.0
+toml==0.10.2
+typing-extensions==3.7.4.3
+wrapt==1.12.1

serial_monitor/serial_monitor.py

@@ -0,0 +1,44 @@
+import glob
+import argparse
+import serial
+
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--port")
+    args = parser.parse_args()
+
+    # Get all the valid serial ports available.
+    available_ports = glob.glob("/dev/cu.*")
+
+    # Only do this if the user did not specify a port.
+    if args.port is None:
+        # Make the user select a port to start a listening session.
+        print("Available ports:")
+        for i, port in enumerate(available_ports):
+            print(f"{i} - {port}")
+
+    selected_port_index = None
+    while selected_port_index is None and args.port is None:
+        try:
+            selected_port_index = input(
+                "\nType port number to start listening section: "
+            )
+            selected_port_index = int(selected_port_index)
+            if selected_port_index < 0 or selected_port_index >= len(available_ports):
+                print("The port number you provided does not exist.")
+                selected_port_index = None
+        except:
+            print("The typed input is not valid, please enter a valid number.")
+            selected_port_index = None
+
+    port = args.port if args.port is not None else available_ports[selected_port_index]
+    # TODO: Allow selecting baud raute, 115200 by default for now.
+    with serial.Serial(port, 115200) as ser:
+        while True:
+            byte = ser.read()
+            print(byte.decode("utf-8"), end="")
+
+
+if __name__ == "__main__":
+    main()