From ac4f0d410f58705cbce22c180df0e2653c32fedd Mon Sep 17 00:00:00 2001
From: logicog <git@logicog.de>
Date: Tue, 14 Oct 2025 19:17:12 +0200
Subject: [PATCH 1/6] Add CRC16 initial code

---
 Makefile        |   5 +-
 crc16.asm       | 121 ++++++++++++++++++++++++++++++++++++++++++++++++
 rtlplayground.c |  72 ++++++++++++++++++++--------
 3 files changed, 177 insertions(+), 21 deletions(-)
 create mode 100644 crc16.asm

diff --git a/Makefile b/Makefile
index 613a0c3..4cea7b8 100644
--- a/Makefile
+++ b/Makefile
@@ -40,6 +40,9 @@ clean:
 $(BUILDDIR)crtstart.rel: crtstart.asm
 	$(ASM) $(AFLAGS) -o $@ $<
 
+$(BUILDDIR)crc16.rel: crc16.asm
+	$(ASM) $(AFLAGS) -o $@ $<
+
 $(BUILDDIR)%.rel: %.c
 	$(CC) $(CC_FLAGS) -o $@ -c $<
 
@@ -47,7 +50,7 @@ $(BUILDDIR)%.rel: $(BUILDDIR)%.asm
 	${ASM} ${AFLAGS} -o $@ $<
 #	mv -f $(addprefix $(basename $^), .lst .rel .sym) .
 
-$(BUILDDIR)rtlplayground.ihx: $(BUILDDIR)crtstart.rel $(OBJS)
+$(BUILDDIR)rtlplayground.ihx: $(BUILDDIR)crtstart.rel $(OBJS) $(BUILDDIR)crc16.rel
 	$(CC) $(CC_FLAGS) -Wl-bHOME=${BOOTLOADER_ADDRESS}  -Wl-bBANK1=0x14000 -Wl-r -o $@ $^
 
 $(BUILDDIR)rtlplayground.img: $(BUILDDIR)rtlplayground.ihx
diff --git a/crc16.asm b/crc16.asm
new file mode 100644
index 0000000..4f1be7a
--- /dev/null
+++ b/crc16.asm
@@ -0,0 +1,121 @@
+;
+; CRC16 calculation module
+;
+	.globl 	_crc_value
+	.globl 	_crc16
+	.equ	BANK, 0x96
+;	.equ	DPS, 0x86
+; Variable in XMEM holding current CRC16 value, being updated
+	.area XSEG    (XDATA)
+_crc_value::
+	.ds 2
+
+;-------------------------------------------------------
+; CRC16 subroutine
+; - dptr points to byte to be CRCd in xmem
+; - algorithm uses table lookup
+;-------------------------------------------------------
+	.area HOME    (CODE)
+	.area CSEG    (CODE)
+;	.area BANK1   (CODE)
+_crc16:
+	mov	BANK, #1
+	push	dph
+	push	dpl
+	movx	a, @dptr
+;	inc	DPS
+	mov	b, a
+	mov	dptr, #_crc_value
+	movx	a, @dptr
+
+	xrl	a, b 			; create index into tables
+	push	a 			; save index
+	mov	dptr, #crc16_table_l 	; low part of table address
+	movc	a, @a+dptr		; get low byte
+	mov	b, a
+
+	mov	dptr, #_crc_value + 1
+	movx	a, @dptr
+
+	xrl	a, b
+	mov	dptr, #_crc_value
+	movx	@dptr, a		; save result low part
+	mov	dptr, #crc16_table_h	; high part of table address
+	pop	a			; restore index
+	movc	a, @a+dptr
+	mov	dptr, #_crc_value+1
+	movx	@dptr, a		; save result high part
+	pop	dpl
+	pop	dph
+;	clr	DPS
+	ret
+
+	.area BANK1   (CODE)
+
+crc16_table_l:
+	.byte #0x00, #0xc1, #0x81, #0x40, #0x01, #0xc0, #0x80, #0x41
+	.byte #0x01, #0xc0, #0x80, #0x41, #0x00, #0xc1, #0x81, #0x40
+	.byte #0x01, #0xc0, #0x80, #0x41, #0x00, #0xc1, #0x81, #0x40
+	.byte #0x00, #0xc1, #0x81, #0x40, #0x01, #0xc0, #0x80, #0x41
+	.byte #0x01, #0xc0, #0x80, #0x41, #0x00, #0xc1, #0x81, #0x40
+	.byte #0x00, #0xc1, #0x81, #0x40, #0x01, #0xc0, #0x80, #0x41
+	.byte #0x00, #0xc1, #0x81, #0x40, #0x01, #0xc0, #0x80, #0x41
+	.byte #0x01, #0xc0, #0x80, #0x41, #0x00, #0xc1, #0x81, #0x40
+	.byte #0x01, #0xc0, #0x80, #0x41, #0x00, #0xc1, #0x81, #0x40
+	.byte #0x00, #0xc1, #0x81, #0x40, #0x01, #0xc0, #0x80, #0x41
+	.byte #0x00, #0xc1, #0x81, #0x40, #0x01, #0xc0, #0x80, #0x41
+	.byte #0x01, #0xc0, #0x80, #0x41, #0x00, #0xc1, #0x81, #0x40
+	.byte #0x00, #0xc1, #0x81, #0x40, #0x01, #0xc0, #0x80, #0x41
+	.byte #0x01, #0xc0, #0x80, #0x41, #0x00, #0xc1, #0x81, #0x40
+	.byte #0x01, #0xc0, #0x80, #0x41, #0x00, #0xc1, #0x81, #0x40
+	.byte #0x00, #0xc1, #0x81, #0x40, #0x01, #0xc0, #0x80, #0x41
+	.byte #0x01, #0xc0, #0x80, #0x41, #0x00, #0xc1, #0x81, #0x40
+	.byte #0x00, #0xc1, #0x81, #0x40, #0x01, #0xc0, #0x80, #0x41
+	.byte #0x00, #0xc1, #0x81, #0x40, #0x01, #0xc0, #0x80, #0x41
+	.byte #0x01, #0xc0, #0x80, #0x41, #0x00, #0xc1, #0x81, #0x40
+	.byte #0x00, #0xc1, #0x81, #0x40, #0x01, #0xc0, #0x80, #0x41
+	.byte #0x01, #0xc0, #0x80, #0x41, #0x00, #0xc1, #0x81, #0x40
+	.byte #0x01, #0xc0, #0x80, #0x41, #0x00, #0xc1, #0x81, #0x40
+	.byte #0x00, #0xc1, #0x81, #0x40, #0x01, #0xc0, #0x80, #0x41
+	.byte #0x00, #0xc1, #0x81, #0x40, #0x01, #0xc0, #0x80, #0x41
+	.byte #0x01, #0xc0, #0x80, #0x41, #0x00, #0xc1, #0x81, #0x40
+	.byte #0x01, #0xc0, #0x80, #0x41, #0x00, #0xc1, #0x81, #0x40
+	.byte #0x00, #0xc1, #0x81, #0x40, #0x01, #0xc0, #0x80, #0x41
+	.byte #0x01, #0xc0, #0x80, #0x41, #0x00, #0xc1, #0x81, #0x40
+	.byte #0x00, #0xc1, #0x81, #0x40, #0x01, #0xc0, #0x80, #0x41
+	.byte #0x00, #0xc1, #0x81, #0x40, #0x01, #0xc0, #0x80, #0x41
+	.byte #0x01, #0xc0, #0x80, #0x41, #0x00, #0xc1, #0x81, #0x40
+
+crc16_table_h:
+	.byte #0x00, #0xc0, #0xc1, #0x01, #0xc3, #0x03, #0x02, #0xc2
+	.byte #0xc6, #0x06, #0x07, #0xc7, #0x05, #0xc5, #0xc4, #0x04
+	.byte #0xcc, #0x0c, #0x0d, #0xcd, #0x0f, #0xcf, #0xce, #0x0e
+	.byte #0x0a, #0xca, #0xcb, #0x0b, #0xc9, #0x09, #0x08, #0xc8
+	.byte #0xd8, #0x18, #0x19, #0xd9, #0x1b, #0xdb, #0xda, #0x1a
+	.byte #0x1e, #0xde, #0xdf, #0x1f, #0xdd, #0x1d, #0x1c, #0xdc
+	.byte #0x14, #0xd4, #0xd5, #0x15, #0xd7, #0x17, #0x16, #0xd6
+	.byte #0xd2, #0x12, #0x13, #0xd3, #0x11, #0xd1, #0xd0, #0x10
+	.byte #0xf0, #0x30, #0x31, #0xf1, #0x33, #0xf3, #0xf2, #0x32
+	.byte #0x36, #0xf6, #0xf7, #0x37, #0xf5, #0x35, #0x34, #0xf4
+	.byte #0x3c, #0xfc, #0xfd, #0x3d, #0xff, #0x3f, #0x3e, #0xfe
+	.byte #0xfa, #0x3a, #0x3b, #0xfb, #0x39, #0xf9, #0xf8, #0x38
+	.byte #0x28, #0xe8, #0xe9, #0x29, #0xeb, #0x2b, #0x2a, #0xea
+	.byte #0xee, #0x2e, #0x2f, #0xef, #0x2d, #0xed, #0xec, #0x2c
+	.byte #0xe4, #0x24, #0x25, #0xe5, #0x27, #0xe7, #0xe6, #0x26
+	.byte #0x22, #0xe2, #0xe3, #0x23, #0xe1, #0x21, #0x20, #0xe0
+	.byte #0xa0, #0x60, #0x61, #0xa1, #0x63, #0xa3, #0xa2, #0x62
+	.byte #0x66, #0xa6, #0xa7, #0x67, #0xa5, #0x65, #0x64, #0xa4
+	.byte #0x6c, #0xac, #0xad, #0x6d, #0xaf, #0x6f, #0x6e, #0xae
+	.byte #0xaa, #0x6a, #0x6b, #0xab, #0x69, #0xa9, #0xa8, #0x68
+	.byte #0x78, #0xb8, #0xb9, #0x79, #0xbb, #0x7b, #0x7a, #0xba
+	.byte #0xbe, #0x7e, #0x7f, #0xbf, #0x7d, #0xbd, #0xbc, #0x7c
+	.byte #0xb4, #0x74, #0x75, #0xb5, #0x77, #0xb7, #0xb6, #0x76
+	.byte #0x72, #0xb2, #0xb3, #0x73, #0xb1, #0x71, #0x70, #0xb0
+	.byte #0x50, #0x90, #0x91, #0x51, #0x93, #0x53, #0x52, #0x92
+	.byte #0x96, #0x56, #0x57, #0x97, #0x55, #0x95, #0x94, #0x54
+	.byte #0x9c, #0x5c, #0x5d, #0x9d, #0x5f, #0x9f, #0x9e, #0x5e
+	.byte #0x5a, #0x9a, #0x9b, #0x5b, #0x99, #0x59, #0x58, #0x98
+	.byte #0x88, #0x48, #0x49, #0x89, #0x4b, #0x8b, #0x8a, #0x4a
+	.byte #0x4e, #0x8e, #0x8f, #0x4f, #0x8d, #0x4d, #0x4c, #0x8c
+	.byte #0x44, #0x84, #0x85, #0x45, #0x87, #0x47, #0x46, #0x86
+	.byte #0x82, #0x42, #0x43, #0x83, #0x41, #0x81, #0x80, #0x40
diff --git a/rtlplayground.c b/rtlplayground.c
index 5ce107c..b3c77fd 100644
--- a/rtlplayground.c
+++ b/rtlplayground.c
@@ -16,6 +16,10 @@
 #include "uip/uip.h"
 #include "uip/uip_arp.h"
 
+extern __xdata uint16_t crc_value;
+__xdata uint8_t crc_testbytes[10];
+void crc16(__xdata uint8_t *v) __naked;
+
 // Upload Firmware to 1M
 #define FIRMWARE_UPLOAD_START 0x100000
 
@@ -1705,37 +1709,65 @@ void bootloader(void)
 	flash_read_bulk(flash_buf);
 
 	if (flash_buf[0] == 0x00 && flash_buf[1] == 0x40) {
-		print_string("Update in progress, moving firmware to start of FLASH!\n");
-
 		__xdata uint32_t dest = 0x0;
 		__xdata uint32_t source = FIRMWARE_UPLOAD_START;
-		// A 512kByte = 4MBit Flash has 128*8=1024 512k blocks, we copy only 120
-		for (__xdata uint16_t i=0; i < 960; i++) {
-			print_string("Writing block: ");
-			print_short(dest);
+		__xdata uint16_t i = 0;
+		__xdata uint16_t j = 0;
+		__xdata uint8_t * __xdata bptr;
+		print_string("Identified update image. Checking integrity...\n");
+
+		crc_value = 0x0000;
+		for (i = 0; i < 1024; i++) {
 			flash_region.addr = source;
 			flash_region.len = 0x200;
 			flash_read_bulk(flash_buf);
-			write_char('\n');
-			if (!(i & 0x7)) {
-				flash_region.addr = dest;
-				flash_sector_erase();
-			}
-			flash_region.addr = dest;
-			flash_region.len = 0x200;
-			flash_write_bytes(flash_buf);
-			dest += 0x200;
+			bptr = flash_buf;
+			for (j = 0; j < 0x200; j++)
+				crc16(bptr++);
 			source += 0x200;
+			print_short(crc_value); write_char(' ');
 		}
-		print_string("Deleting uploaded flash image\n");
+		if (crc_value == 0xb001) {
+			print_string("Checksum OK\n");
+			print_string("Update in progress, moving firmware to start of FLASH!\n");
+			source = FIRMWARE_UPLOAD_START;
+			// A 512kByte = 4MBit Flash has 128*8=1024 512k blocks, we copy only 120
+			for (i = 0; i < 960; i++) {
+				print_string("Writing block: ");
+				print_short(dest);
+				flash_region.addr = source;
+				flash_region.len = 0x200;
+				flash_read_bulk(flash_buf);
+				write_char('\n');
+				if (!(i & 0x7)) {
+					flash_region.addr = dest;
+					flash_sector_erase();
+				}
+				flash_region.addr = dest;
+				flash_region.len = 0x200;
+				flash_write_bytes(flash_buf);
+				dest += 0x200;
+				source += 0x200;
+			}
+			print_string("Deleting uploaded flash image\n");
+			dest = FIRMWARE_UPLOAD_START;
+			for (register uint8_t i=0; i < 128; i++) {
+				flash_region.addr = dest;			
+				flash_sector_erase();
+				dest += 0x1000;
+			}
+			print_string("Resetting now");
+			delay(200);
+			reset_chip();
+		}
+		print_string("Checksum incorrect, please upload the image again\n");
+		print_string("Erasing bad uploaded flash image\n");
 		dest = FIRMWARE_UPLOAD_START;
-		for (register uint8_t i=0; i < 120; i++) {
-			flash_region.addr = dest;			
+		for (register uint8_t i=0; i < 128; i++) {
+			flash_region.addr = dest;
 			flash_sector_erase();
 			dest += 0x1000;
 		}
-		print_string("Resetting now");
-		reset_chip();
 	}
 
 	// Reset NIC

From 8499e9e46448cba99d9fb93e89d2c0dd5cb63740 Mon Sep 17 00:00:00 2001
From: logicog <git@logicog.de>
Date: Wed, 15 Oct 2025 20:17:34 +0200
Subject: [PATCH 2/6] Add CRC-16 calculator for a firmware image

---
 tools/Makefile         |   5 +-
 tools/crc_calculator.c | 179 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 183 insertions(+), 1 deletion(-)
 create mode 100644 tools/crc_calculator.c

diff --git a/tools/Makefile b/tools/Makefile
index 87333ed..cca21a7 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -2,7 +2,7 @@ CC = gcc
 CCFLAGS = -Wall -o
 BUILDDIR = output/
 
-all: create_build_dir $(BUILDDIR)injector $(BUILDDIR)fileadder $(BUILDDIR)httpd_sim
+all: create_build_dir $(BUILDDIR)injector $(BUILDDIR)fileadder $(BUILDDIR)httpd_sim $(BUILDDIR)crc_calculator
 
 create_build_dir:
 	mkdir -p $(BUILDDIR)
@@ -16,5 +16,8 @@ $(BUILDDIR)injector: injector.c
 $(BUILDDIR)fileadder: fileadder.c
 	gcc $^ $(CCFLAGS) $@
 
+$(BUILDDIR)crc_calculator: crc_calculator.c
+	gcc $^ $(CCFLAGS) $@
+
 $(BUILDDIR)httpd_sim: httpd_sim.c httpd_sim.h
 	gcc $< $(CCFLAGS) $@ -I/usr/include/json-c -ljson-c
diff --git a/tools/crc_calculator.c b/tools/crc_calculator.c
new file mode 100644
index 0000000..4089fea
--- /dev/null
+++ b/tools/crc_calculator.c
@@ -0,0 +1,179 @@
+/*
+ * Calculator for the CRC16 as described in AN27 by Dallas Semiconductor
+ * http://www.microshadow.com/files/files8051/app27.pdf
+ * The implementation in C is based on the code given in
+ * https://carta.tech/man-pages/man3/_crc_ibutton_update.3avr.html
+ * The polynomial of the CRC is 0xa001: x^16 + x^15 + x^2 + 1
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <argp.h>
+#include <string.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+
+// Use a 4MB buffer, the same as the flash rom size
+#define BUFFER_SIZE 0x400000
+char buffer[BUFFER_SIZE];
+
+struct arguments {
+	char *input_file;
+	char *output_file;
+	bool update;
+	bool verify;
+};
+
+const char *argp_program_version = "crc_calculator 0.1";
+const char *argp_program_bug_address = "https://github.com/logicog/RTLPlayground/issues";
+static char doc[] = "Calculate (and optionally update) the CRC of an image";
+static char args_doc[] = "crc_calculator [options] INPUT_IMAGE";
+static struct argp_option options[] = {
+    { "output", 'o', "FILE", 0, "Output image file name instead of overwriting input image"},
+    { "update", 'u', 0, OPTION_ARG_OPTIONAL, "Update the image with the CRC"},
+    { "verify", 'v', 0, OPTION_ARG_OPTIONAL, "Verify the CRC of the file"},
+    { 0 }
+};
+
+
+uint16_t crc16_update(uint16_t crc, uint8_t a)
+{
+    crc ^= a;
+    for (int i = 0; i < 8; ++i)
+	    crc = crc & 1 ? (crc >> 1) ^ 0xA001 : crc >> 1;
+
+    return crc;
+}
+
+
+static error_t parse_opt(int key, char *arg, struct argp_state *state)
+{
+	struct arguments *arguments = state->input;
+	switch (key) {
+	case 'u':
+		arguments->update = true;
+		break;
+	case 'v':
+		arguments->verify = true;
+		break;
+	case 'o':
+		arguments->output_file = arg;
+		break;
+	default:
+		return ARGP_ERR_UNKNOWN;
+    }
+    return 0;
+}
+
+
+static struct argp argp = {
+	options, parse_opt, args_doc, doc, 0, 0, 0
+};
+
+
+int main(int argc, char **argv)
+{
+	struct arguments arguments;
+	int arg_index;
+	char tmpfilename[] = "crc_XXXXXX";
+	uint16_t crc = 0;
+	FILE *inptr;
+	int outptr;
+	int range;
+
+	arguments.input_file = NULL;
+	arguments.output_file = NULL;
+	arguments.update = false;
+	arguments.verify = false;
+
+	argp_parse(&argp, argc, argv, 0, &arg_index, &arguments);
+	if (!arg_index)
+		argp_usage (0);
+
+	memset(buffer, 0, BUFFER_SIZE);
+
+	size_t filesize = 0;
+	if (argv[arg_index]) {
+		inptr = fopen(argv[arg_index], "rb");
+		if (inptr == NULL) {
+			printf("Cannot open input file %s\n", argv[arg_index]);
+			return 5;
+		}
+
+		fseek(inptr, 0L, SEEK_END);
+		filesize = ftell(inptr);
+		rewind(inptr);
+		printf("Input file size: %ld\n", filesize);
+		if (filesize > BUFFER_SIZE) {
+			printf("File too large.\n");
+			return 5;
+		}
+		size_t bytes_read = fread(buffer, 1, sizeof(buffer), inptr);
+
+		printf("Bytes read: %ld\n", bytes_read);
+
+		if (bytes_read != filesize) {
+			printf("Error reading input file.\n");
+			return 5;
+		}
+		fclose(inptr);
+	}
+
+	range = filesize;
+	if (!arguments.verify) {
+		if (arguments.update) {
+			range -= 2;
+		} else if (arguments.output_file) {
+			filesize += 2;
+		}
+	}
+
+	for (int i = 0; i < range; i++)
+		crc = crc16_update(crc, buffer[i]);
+
+	printf("CRC16 is: 0x%04x\n", crc);
+
+	if (arguments.verify) {
+		if (crc == 0xb001) {
+			printf("Checksum OK\n");
+			return 0;
+		} else {
+			printf("Checksum Incorrect\n");
+			return 5;
+		}
+	}
+
+	// We have to create a new image with updated CRC
+	if (arguments.update || arguments.output_file) {
+		crc ^= 0xffff;
+		printf("Setting CRC bytes at position: 0x%x to CRC 1s complement 0x%04x\n", range, crc);
+		// The CRC algorithm expects as input always first the LO-Byte
+		buffer[range] = crc;
+		buffer[range + 1] = crc >> 8;
+
+		if (!arguments.update)
+			outptr = creat(arguments.output_file, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
+		else
+			outptr = mkstemp(tmpfilename);
+
+		if (!outptr) {
+			printf("Cannot open %s\n", arguments.output_file);
+			return 5;
+		}
+		size_t written = write(outptr, buffer, filesize);
+
+		if (written != filesize) {
+			printf("Error writing output file.\n");
+			return 5;
+		}
+		close(outptr);
+
+		if (arguments.update)
+			rename(tmpfilename, argv[arg_index]);
+	}
+
+	return 0;
+}

From 4d17d9ff001ee938e99e39ccf86e45762eaa5ac6 Mon Sep 17 00:00:00 2001
From: logicog <git@logicog.de>
Date: Wed, 15 Oct 2025 20:21:58 +0200
Subject: [PATCH 3/6] Add CRC verification

---
 httpd/httpd.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/httpd/httpd.c b/httpd/httpd.c
index 289308a..ab135a4 100644
--- a/httpd/httpd.c
+++ b/httpd/httpd.c
@@ -49,6 +49,9 @@ __xdata uint16_t short_parsed;
 #define TSTATE_CLOSED 	3
 #define TSTATE_POST 	4
 
+extern __xdata uint16_t crc_value;
+void crc16(__xdata uint8_t *v) __naked;
+
 
 inline uint8_t is_separator(uint8_t c)
 {
@@ -224,6 +227,12 @@ uint8_t stream_upload(uint16_t bptr)
 			uptr += write_len;
 			write_len = 0;
 			// TODO: This is a bit premature, what about a nice web-page saying the device will reset???
+			print_string("CRC16: "); print_short(crc_value); write_char('\n');
+			if (crc_value == 0xb001) {
+				print_string("Checksum OK.");
+			} else {
+				print_string("Checksum incorrect!");
+			}
 			print_string("Upload to flash done, will reset!\n");
 			reset_chip();
 			if (bptr >= uip_len)
@@ -231,6 +240,7 @@ uint8_t stream_upload(uint16_t bptr)
 			return 1;
 		}
 		if (p[bptr] == boundary[bindex]) {
+			crc16(p + bptr);
 			bptr++;
 			bindex++;
 		} else {
@@ -239,6 +249,7 @@ uint8_t stream_upload(uint16_t bptr)
 				write_len += bindex;
 				bindex = 0;
 			}
+			crc16(p + bptr);
 			flash_buf[write_len++] = p[bptr++];
 			if (write_len >= FLASHMEM_PAGE_SIZE) {
 				print_string("len: "); print_short(write_len); write_char(' ');
@@ -313,6 +324,7 @@ void handle_post(void)
 		p += 4; // Skip \r\n\r\n sequence at end of preamble of part
 
 		uptr = FIRMWARE_UPLOAD_START;
+		crc_value = 0;
 		bindex = 0;
 		write_len = 0;
 		stream_upload(p - uip_appdata);

From f3ff8eed428e96e4da7fea195e54a62564f4f1e1 Mon Sep 17 00:00:00 2001
From: logicog <git@logicog.de>
Date: Wed, 15 Oct 2025 20:25:09 +0200
Subject: [PATCH 4/6] Make use of CRC checksum calculation when building image

---
 Makefile | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Makefile b/Makefile
index 4cea7b8..11f9293 100644
--- a/Makefile
+++ b/Makefile
@@ -64,6 +64,7 @@ $(BUILDDIR)rtlplayground.bin: $(BUILDDIR)rtlplayground.img
 	dd if=$< skip=80 bs=1024 >>$@
 	tools/$(BUILDDIR)fileadder -a $(CONFIG_LOCATION) -s $(IMAGESIZE) -d config.txt $@
 	tools/$(BUILDDIR)fileadder -a $(HTML_LOCATION) -s $(IMAGESIZE) -d html -p html_data $@
+	tools/$(BUILDDIR)crc_calculator -u $@
 
 
 .PHONY: clean all $(SUBDIRS)

From 9c062edc753d52415d2360736c2328d159e0fb87 Mon Sep 17 00:00:00 2001
From: logicog <git@logicog.de>
Date: Sun, 26 Oct 2025 14:20:07 +0100
Subject: [PATCH 5/6] Fix CRC calculation during upload

---
 httpd/httpd.c | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/httpd/httpd.c b/httpd/httpd.c
index ab135a4..950e5f4 100644
--- a/httpd/httpd.c
+++ b/httpd/httpd.c
@@ -50,6 +50,7 @@ __xdata uint16_t short_parsed;
 #define TSTATE_POST 	4
 
 extern __xdata uint16_t crc_value;
+__xdata uint16_t crc_final;
 void crc16(__xdata uint8_t *v) __naked;
 
 
@@ -187,13 +188,15 @@ __xdata uint8_t *scan_header(__xdata uint8_t *p)
 		content_type += 30;
 		uint8_t i = 0;
 		while (content_type[i] != '\r' && content_type[i] != '\n') {
-			boundary[i + 2] = content_type[i];
+			boundary[i + 4] = content_type[i];
 			i++;
 		}
-		// The boundary between parts is "--" + the boundary given in the header
-		boundary[0] = '-';
-		boundary[1] = '-';
-		boundary[i + 2] = 0;
+		// The boundary between parts is "\r\n--" + the boundary given in the header
+		boundary[0] = '\r';
+		boundary[1] = '\n';
+		boundary[2] = '-';
+		boundary[3] = '-';
+		boundary[i + 4] = 0;
 	}
 	return p;
 }
@@ -227,8 +230,8 @@ uint8_t stream_upload(uint16_t bptr)
 			uptr += write_len;
 			write_len = 0;
 			// TODO: This is a bit premature, what about a nice web-page saying the device will reset???
-			print_string("CRC16: "); print_short(crc_value); write_char('\n');
-			if (crc_value == 0xb001) {
+			print_string("CRC16: "); print_short(crc_final); write_char('\n');
+			if (crc_final == 0xb001) {
 				print_string("Checksum OK.");
 			} else {
 				print_string("Checksum incorrect!");
@@ -240,6 +243,8 @@ uint8_t stream_upload(uint16_t bptr)
 			return 1;
 		}
 		if (p[bptr] == boundary[bindex]) {
+			if (!bindex)
+				crc_final = crc_value;
 			crc16(p + bptr);
 			bptr++;
 			bindex++;
@@ -253,6 +258,7 @@ uint8_t stream_upload(uint16_t bptr)
 			flash_buf[write_len++] = p[bptr++];
 			if (write_len >= FLASHMEM_PAGE_SIZE) {
 				print_string("len: "); print_short(write_len); write_char(' ');
+				print_string("CRC16: "); print_short(crc_value); write_char('\n');
 				flash_region.addr = uptr;
 				flash_region.len = FLASHMEM_PAGE_SIZE;
 				flash_write_bytes(flash_buf);

From eb0e4df5ea4d1aec92e46dae8ac6217167f9fba8 Mon Sep 17 00:00:00 2001
From: logicog <git@logicog.de>
Date: Sun, 26 Oct 2025 14:20:30 +0100
Subject: [PATCH 6/6] Fix reset after image upload

---
 rtlplayground.c | 44 ++++++++++++++++++++++++--------------------
 1 file changed, 24 insertions(+), 20 deletions(-)

diff --git a/rtlplayground.c b/rtlplayground.c
index b3c77fd..5b59d75 100644
--- a/rtlplayground.c
+++ b/rtlplayground.c
@@ -1044,6 +1044,7 @@ void sleep(uint16_t t)
 void reset_chip(void)
 {
 	REG_SET(RTL837X_REG_RESET, 1);
+	while(1);
 }
 
 
@@ -1703,6 +1704,24 @@ void bootloader(void)
 	print_string("  Flash controller\n");
 	flash_init(0);
 
+	// Reset NIC
+	reg_bit_set(0x24, 2);
+	do {
+		reg_read(0x24);
+	} while (SFR_DATA_0 & 0x4);
+	print_string("NIC reset\n");
+
+	uip_ipaddr(&uip_hostaddr, ownIP[0], ownIP[1], ownIP[2], ownIP[3]);
+	uip_ipaddr(&uip_draddr, gatewayIP[0], gatewayIP[1], gatewayIP[2], gatewayIP[3]);
+	uip_ipaddr(&uip_netmask, netmask[0], netmask[1], netmask[2], netmask[3]);
+
+	REG_SET(0x7f94, 0x0);
+	if (isRTL8373)
+		rtl8373_init();
+	else
+		rtl8372_init();
+	delay(1000);
+
 	// Check update in progress and move blocks
 	flash_region.addr = FIRMWARE_UPLOAD_START;
 	flash_region.len = 0x100;
@@ -1722,10 +1741,13 @@ void bootloader(void)
 			flash_region.len = 0x200;
 			flash_read_bulk(flash_buf);
 			bptr = flash_buf;
-			for (j = 0; j < 0x200; j++)
+			for (j = 0; j < 0x200; j++) {
+				print_byte(*bptr); write_char(' ');
 				crc16(bptr++);
+				print_short(crc_value); write_char(':');
+			}
 			source += 0x200;
-			print_short(crc_value); write_char(' ');
+			write_char('\n'); print_short(crc_value); write_char(' ');
 		}
 		if (crc_value == 0xb001) {
 			print_string("Checksum OK\n");
@@ -1770,24 +1792,6 @@ void bootloader(void)
 		}
 	}
 
-	// Reset NIC
-	reg_bit_set(0x24, 2);
-	do {
-		reg_read(0x24);
-	} while (SFR_DATA_0 & 0x4);
-	print_string("NIC reset\n");
-
-	uip_ipaddr(&uip_hostaddr, ownIP[0], ownIP[1], ownIP[2], ownIP[3]);
-	uip_ipaddr(&uip_draddr, gatewayIP[0], gatewayIP[1], gatewayIP[2], gatewayIP[3]);
-	uip_ipaddr(&uip_netmask, netmask[0], netmask[1], netmask[2], netmask[3]);
-
-	REG_SET(0x7f94, 0x0);
-	if (isRTL8373)
-		rtl8373_init();
-	else
-		rtl8372_init();
-	delay(1000);
-
 #ifdef DEBUG
 	// This register seems to work on the RTL8373 only if also the SDS
 	// Is correctly configured. Therefore, we can test it, here...