diff --git a/cmd_parser.c b/cmd_parser.c
index 0b8f97a..35fd791 100644
--- a/cmd_parser.c
+++ b/cmd_parser.c
@@ -803,47 +803,27 @@ void cmd_parser(void) __banked
 			}
 		} else if (cmd_compare(0, "stat")) {
 			port_stats_print();
-		} else if (cmd_compare(0, "flash") && cmd_words_b[1] > 0 && cmd_buffer[cmd_words_b[1]] == 'r') {
-			print_string("\nPRINT SECURITY REGISTERS\n");
+		} else if (cmd_compare(0, "flash") && cmd_words_b[1] > 0 && cmd_buffer[cmd_words_b[1]] == 's') {
+			print_string("\nSECURITY REGISTERS\n");
 			// The following will only show something else than 0xff if it was programmed for a managed switch
+			print_string("Region 1: ");
 			flash_region.addr = 0x0001000;
 			flash_region.len = 40;
 			flash_read_security();
+			print_string("\nRegion 2: ");
 			flash_region.addr = 0x0002000;
 			flash_region.len = 40;
 			flash_read_security();
+			print_string("\nRegion 3: ");
 			flash_region.addr = 0x0003000;
 			flash_region.len = 40;
 			flash_read_security();
-		} else if (cmd_compare(0, "flash") && cmd_words_b[1] > 0 && cmd_buffer[cmd_words_b[1]] == 'd') {
-			print_string("\nDUMPING FLASH\n");
-			flash_region.addr = 0;
-			flash_region.len = 255;
-			flash_dump(255);
 		} else if (cmd_compare(0, "flash") && cmd_words_b[1] > 0 && cmd_buffer[cmd_words_b[1]] == 'j') {
 			print_string("\nJEDEC ID\n");
 			flash_read_jedecid();
 		} else if (cmd_compare(0, "flash") && cmd_words_b[1] > 0 && cmd_buffer[cmd_words_b[1]] == 'u') {
-			print_string("\nUNIQUE ID\n");
+			print_string("\nUNIQUE ID (note: only 4 bytes are likely correct here!)\n");
 			flash_read_uid();
-		} else if (cmd_compare(0, "flash") && cmd_words_b[1] > 0 && cmd_buffer[cmd_words_b[1]] == 's') {
-			print_string("\nFLASH FAST MODE\n"); // Switch to flash 62.5 MHz mode
-			flash_init(1);
-			print_string("\nNow dumping flash\n");
-			flash_region.addr = 0;
-			flash_region.len = 255;
-			flash_dump(255);
-		} else if (cmd_compare(0, "flash") && cmd_words_b[1] > 0 && cmd_buffer[cmd_words_b[1]] == 'e') {
-			print_string("\nFLASH erase\n");
-			flash_region.addr = 0x20000;
-			flash_sector_erase();
-		} else if (cmd_compare(0, "flash") && cmd_words_b[1] > 0 && cmd_buffer[cmd_words_b[1]] == 'w') {
-			print_string("\nFLASH write\n");
-			for (uint8_t i = 0; i < 20; i++)
-				flash_buf[i] = greeting[i];
-			flash_region.addr = 0x200000;
-			flash_region.len = 20;
-			flash_write_bytes(flash_buf);
 		} else if (cmd_compare(0, "port") && cmd_words_b[1] > 0) {
 			parse_port();
 		} else if (cmd_compare(0, "mtu") && cmd_words_b[1] > 0) {
diff --git a/httpd/httpd.c b/httpd/httpd.c
index 7b9cd47..2812524 100644
--- a/httpd/httpd.c
+++ b/httpd/httpd.c
@@ -27,6 +27,7 @@ extern __code uint8_t * __code hex;
 extern __code struct f_data f_data[];
 extern __code char * __code mime_strings[];
 extern __xdata struct flash_region_t flash_region;
+extern __xdata uint32_t flash_size;
 
 // Flash buffer to optimize flash writing speed, write_len is the current filling position
 extern __xdata uint8_t flash_buf[FLASH_BUF_SIZE];
@@ -426,6 +427,12 @@ void handle_post(void)
 		p += 4; // Skip \r\n\r\n sequence at end of preamble of part
 
 		if (is_word(request_path, "upload")) {
+			if (flash_size < FIRMWARE_UPLOAD_START*2)
+			{
+				print_string("Flash too small for firmware upload!\n");
+				send_bad_request();
+				return;
+			}
 			print_string("Firmware upload started.");
 			uptr = FIRMWARE_UPLOAD_START;
 			verify_crc = 1;
diff --git a/rtl837x_flash.c b/rtl837x_flash.c
index 00f7cb5..76c6eb3 100644
--- a/rtl837x_flash.c
+++ b/rtl837x_flash.c
@@ -9,7 +9,7 @@
 
 __xdata uint8_t dio_enabled;
 __xdata struct flash_region_t flash_region;
-
+__xdata uint32_t flash_size;
 
 // For the flash commands, see e.g. Windbond W25Q32JV datasheet
 #define CMD_WRITE_STATUS	0x01
@@ -17,8 +17,9 @@ __xdata struct flash_region_t flash_region;
 // Don't use command `READ 0x03`, because on many device this command can't run at maximum SPI-clock speed.
 // Use `Fast READ 0x0b` instead!
 //#define CMD_READ		0x03
+#define CMD_READ_STATUS		0x05
 #define CMD_WRITE_ENABLE	0x06
-#define CMD_FREAD		0x0b
+#define CMD_FREAD			0x0b
 #define CMD_SECTOR_ERASE	0x20
 #define CMD_READ_SECURITY_REGS	0x48
 #define CMD_READ_UNIQUE_ID	0x4b
@@ -87,7 +88,7 @@ uint8_t flash_read_status(void)
 
 	// setup status read command
 	SFR_FLASH_TCONF = 0x11;
-	SFR_FLASH_CMD_R = 5;
+	SFR_FLASH_CMD_R = CMD_READ_STATUS;
 
 	// execute and wait for controller done
 	SFR_FLASH_EXEC_GO = 1;
@@ -119,9 +120,10 @@ void flash_read_uid(void)
 	print_byte(SFR_FLASH_DATA8);
 	print_byte(SFR_FLASH_DATA16);
 	print_byte(SFR_FLASH_DATA24);
+	write_char(' ');
 
+	SFR_FLASH_DUMMYCYCLES = 24;	// Doesn't seem to work; we get the same data as for the first transfer
 	SFR_FLASH_EXEC_GO = 1;
-	SFR_FLASH_DUMMYCYCLES = 24;
 	while(SFR_FLASH_EXEC_BUSY);
 
 	print_byte(SFR_FLASH_DATA0);
@@ -148,15 +150,17 @@ void flash_read_jedecid(void)
 	SFR_FLASH_EXEC_GO = 1;
 	while(SFR_FLASH_EXEC_BUSY);
 
+	print_string("Maufacturer ID: 0x");
 	print_byte(SFR_FLASH_DATA0);
+	print_string("\nMemory Type:    0x");
 	print_byte(SFR_FLASH_DATA8);
-	print_byte(SFR_FLASH_DATA16);
-	print_byte(SFR_FLASH_DATA24);
-
-	// Reset slow read mode
-	SFR_FLASH_MODEB = 0x0;
-	SFR_FLASH_CMD_R = CMD_FREAD;
-	SFR_FLASH_DUMMYCYCLES = 8;
+	print_string("\nCapacity:       0x");
+	uint8_t cap = SFR_FLASH_DATA16;
+	flash_size = 1UL << cap;
+	print_byte(cap);
+	print_string(" = ");
+	print_long(flash_size);
+	print_string(" Bytes\n");
 
 	flash_configure_mmio();
 }
@@ -188,51 +192,6 @@ void flash_write_enable(void)
 	} while (!(status & 0x2));
 }
 
-
-void flash_dump(uint8_t len)
-{
-	short status;
-	do {
-		status = flash_read_status();
-		print_short(status);
-	} while (status & 0x1);
-
-	// Set fast read mode
-	if (dio_enabled) {
-		SFR_FLASH_MODEB = 0x18;
-		SFR_FLASH_CMD_R = CMD_FREAD_DIO;
-		SFR_FLASH_DUMMYCYCLES = 4;
-	} else {
-		SFR_FLASH_MODEB = 0x0;
-		SFR_FLASH_CMD_R = CMD_FREAD;	// Fast read
-		SFR_FLASH_DUMMYCYCLES = 8;	// Add 8 dummy clocks after read?
-	}
-	// Read 4 bytes
-	SFR_FLASH_TCONF = 4;
-	while (len) {
-		SFR_FLASH_ADDR16 = flash_region.addr >> 16;
-		SFR_FLASH_ADDR8 = flash_region.addr >> 8;
-		SFR_FLASH_ADDR0 = flash_region.addr;
-		flash_region.addr += 4;
-
-		SFR_FLASH_EXEC_GO = 1;
-		while(SFR_FLASH_EXEC_BUSY);
-
-		print_short(SFR_FLASH_DATA0);
-		if (len == 1)
-			return;
-		print_short(SFR_FLASH_DATA8);
-		if (len == 2)
-			return;
-		print_short(SFR_FLASH_DATA16);
-		if (len == 3)
-			return;
-		print_short(SFR_FLASH_DATA24);
-
-		len -= 4;
-	}
-}
-
 /*
  * Reads bulk data of length len from the flash memory starging at address src
  * and writes the data into a buffer pointed to by dst in XMEM
@@ -315,7 +274,7 @@ void flash_read_security(void)
 		if (flash_region.len == 3)
 			break;
 		print_byte(SFR_FLASH_DATA24);
-
+		write_char(' ');
 		flash_region.len -= 4;
 	} while(flash_region.len);
 
diff --git a/rtlplayground.c b/rtlplayground.c
index fc0eeed..9d9e755 100644
--- a/rtlplayground.c
+++ b/rtlplayground.c
@@ -24,9 +24,9 @@
 #include "phy.h"
 
 extern __code const struct machine machine;
+extern __xdata uint32_t flash_size;
 
 extern __xdata uint16_t crc_value;
-__xdata uint8_t crc_testbytes[10];
 __xdata struct machine_runtime machine_detected;
 void crc16(__xdata uint8_t *v) __naked;
 
@@ -548,16 +548,6 @@ uint8_t read_flash(uint8_t bank, __code uint8_t *addr)
 	return v;
 }
 
-
-void print_long_x(__xdata uint8_t v[])
-{
-	write_char('0'); write_char('x');
-	for (uint8_t i=0; i < 4; i++) {
-		write_char(hex[v[i] >> 4]);
-		write_char(hex[v[i] & 0xf]);
-	}
-}
-
 /*
  * Read a SerDes register in the SoC
  * Input must be: sds_id = 0/1, page < 128,  reg <= 0xff
@@ -1869,6 +1859,19 @@ void setup_i2c(void)
 
 void check_and_flash_update_image(void)
 {
+	flash_read_jedecid(); // This initializes also __xdata flash_size variable
+
+	print_long(flash_size); print_string(" flash size detected.\n");
+	print_long(FIRMWARE_UPLOAD_START*2); print_string(" bytes needed for update.\n");
+	if (flash_size < FIRMWARE_UPLOAD_START*2) {
+		print_string("Flash too small for updating; skipping update check\n");
+		return;
+	}
+	else {
+		print_string("Flash size ok.\n");
+	}
+
+
 	// Check if an update image is in flash
 	flash_region.addr = FIRMWARE_UPLOAD_START;
 	flash_region.len = 0x100;
@@ -1881,7 +1884,7 @@ void check_and_flash_update_image(void)
 		__xdata uint16_t i = 0;
 		__xdata uint16_t j = 0;
 		__xdata uint8_t * __xdata bptr;
-		print_string("Identified update image. Checking integrity...");
+		print_string("Identified update image. Checking integrity");
 		flash_init(0); // Re-initialize flash for non-DIO operation, otherwise flashing will fail
 		set_sys_led_state(SYS_LED_FAST);
 		crc_value = 0x0000;
@@ -1894,25 +1897,20 @@ void check_and_flash_update_image(void)
 				crc16(bptr++);
 			}
 			source += FLASH_BUF_SIZE;
-			if (i%16 == 0)
-				write_char('.');
+			if (i%16 == 0) write_char('.');
 		}
 		if (crc_value == 0xb001) {
-			print_string("\nChecksum OK\n");
-			print_string("Update in progress, moving firmware to start of FLASH.");
+			print_string("Checksum OK.\nUpdate in progress, moving firmware to start of flash");
 			source = FIRMWARE_UPLOAD_START;
-			// A 512kByte = 4MBit Flash has 128*8=1024 512byte blocks, we copy only 896
-			// (don't overwrite config @ 0x70000)
-			for (i = 0; i < 896; i++) {
-				// print_string("Writing block: ");
-				// print_short(dest);
+			// Don't copy the config area at the end of flash
+			for (i = 0; i < CONFIG_START/FLASH_BUF_SIZE; i++) {
 				flash_region.addr = source;
 				flash_region.len = FLASH_BUF_SIZE;
 				flash_read_bulk(flash_buf);
-				if (!(i & 0x7)) {
+				if (i%8 == 0) {
 					flash_region.addr = dest;
 					flash_sector_erase();
-					write_char('.');
+					if (i%16 == 0) write_char('.');
 				}
 				flash_region.addr = dest;
 				flash_region.len = FLASH_BUF_SIZE;
@@ -1920,15 +1918,16 @@ void check_and_flash_update_image(void)
 				dest += FLASH_BUF_SIZE;
 				source += FLASH_BUF_SIZE;
 			}
-			print_string("\nDeleting uploaded flash image\n");
+			print_string("Done.\nDeleting uploaded flash image");
 			dest = FIRMWARE_UPLOAD_START;
 			for (register uint8_t i=0; i < 128; i++) // TODO: Erasing the entire 512kByte upload area is probably not necessary
 			{
 				flash_region.addr = dest;
 				flash_sector_erase();
 				dest += 0x1000;
+				if (i%4 == 0) write_char('.');
 			}
-			print_string("Resetting now");
+			print_string("Done.\nResetting now");
 			delay(200);
 			reset_chip();
 		}