From 97e468083e02675ea5726cbb8a9afe906df60d44 Mon Sep 17 00:00:00 2001
From: Khairulmizam Samsudin <xource@gmail.com>
Date: Wed, 15 Jun 2022 19:39:26 +0800
Subject: [PATCH 1/3] Fix word-based addressing for dumping EEPROM content

---
 ArduinoISP/ArduinoISP/ArduinoISP.ino | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/ArduinoISP/ArduinoISP/ArduinoISP.ino b/ArduinoISP/ArduinoISP/ArduinoISP.ino
index 18e6561d2..1692db3c6 100644
--- a/ArduinoISP/ArduinoISP/ArduinoISP.ino
+++ b/ArduinoISP/ArduinoISP/ArduinoISP.ino
@@ -549,8 +549,10 @@ char flash_read_page(int length) {
 
 char eeprom_read_page(int length) {
   // here again we have a word address
+  int start = _addr*2;
   for (int x = 0; x < length; x++) {
-    byte ee = spi_transaction(0xA0, 0x00, _addr*2+x, 0xFF);
+    int addr = start +x;
+    byte ee = spi_transaction(0xA0, (addr >> 8) && 0xFF, addr && 0xFF, 0xFF);
     Serial.write( ee);
   }
   return STK_OK;

From 2d8882b886539d28112058337a0c91f743bb45ee Mon Sep 17 00:00:00 2001
From: Khairulmizam Samsudin <xource@gmail.com>
Date: Wed, 15 Jun 2022 21:04:47 +0800
Subject: [PATCH 2/3] Wrong operator

---
 ArduinoISP/ArduinoISP/ArduinoISP.ino | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ArduinoISP/ArduinoISP/ArduinoISP.ino b/ArduinoISP/ArduinoISP/ArduinoISP.ino
index 1692db3c6..7f327e64c 100644
--- a/ArduinoISP/ArduinoISP/ArduinoISP.ino
+++ b/ArduinoISP/ArduinoISP/ArduinoISP.ino
@@ -552,7 +552,7 @@ char eeprom_read_page(int length) {
   int start = _addr*2;
   for (int x = 0; x < length; x++) {
     int addr = start +x;
-    byte ee = spi_transaction(0xA0, (addr >> 8) && 0xFF, addr && 0xFF, 0xFF);
+    byte ee = spi_transaction(0xA0, (addr >> 8) & 0xFF, addr & 0xFF, 0xFF);
     Serial.write( ee);
   }
   return STK_OK;

From 95e99f2ef6102988225375ee55ec0423e7f15b37 Mon Sep 17 00:00:00 2001
From: Khairulmizam Samsudin <xource@gmail.com>
Date: Wed, 15 Jun 2022 21:11:06 +0800
Subject: [PATCH 3/3] Fix word-based addressing for writing EEPROM

---
 ArduinoISP/ArduinoISP/ArduinoISP.ino | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/ArduinoISP/ArduinoISP/ArduinoISP.ino b/ArduinoISP/ArduinoISP/ArduinoISP.ino
index 7f327e64c..e31449975 100644
--- a/ArduinoISP/ArduinoISP/ArduinoISP.ino
+++ b/ArduinoISP/ArduinoISP/ArduinoISP.ino
@@ -488,8 +488,10 @@ byte write_eeprom(int length) {
   // here is a word address, so we use here*2
   // this writes byte-by-byte,
   // page writing may be faster (4 bytes at a time)
+  int start = _addr*2;
   for (int x = 0; x < length; x++) {
-    spi_transaction(0xC0, 0x00, _addr*2+x, buff[x]);
+    int addr = start + x;
+    spi_transaction(0xC0, (addr >> 8) & 0xFF, addr & 0xFF, buff[x]);
     delay(45);
   } 
   return STK_OK;
@@ -497,8 +499,9 @@ byte write_eeprom(int length) {
 
 void program_page() {
   byte result = STK_FAILED;
-  int length = 256 * getch() + getch();
-  if (length > 256) {
+  unsigned int length = 256 * getch();
+  length += getch();
+  if (length > param.eepromsize) {
       Serial.write(STK_FAILED);
       error++;
       return;