From f481d1fbe46d5497ef88d0bd48d56c2439b530f5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20van=20Dorst?= <opensource@vdorst.com>
Date: Thu, 4 Sep 2025 23:49:17 +0200
Subject: [PATCH 01/12] add cmd gpio

---
 cmd_parser.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/cmd_parser.c b/cmd_parser.c
index 7bf6eca..92d317a 100644
--- a/cmd_parser.c
+++ b/cmd_parser.c
@@ -13,6 +13,7 @@
 #include "rtl837x_flash.h"
 #include "rtl837x_phy.h"
 #include "rtl837x_regs.h"
+#include "rtl837x_sfr.h"
 #include "uip/uip.h"
 
 #pragma codeseg BANK1
@@ -423,6 +424,22 @@ void cmd_parser(void) __banked
 		if (cmd_compare(0, "sds")) {
 			print_reg(RTL837X_REG_SDS_MODES);
 		}
+
+		if (cmd_compare(0, "gpio")) {
+			for (uint8_t idx = 0; idx < 3; idx++) {
+				reg_read_m(RTL837X_REG_GPIO_A + (idx * 4));
+				print_string("GPIO ");
+				write_char(idx + 'A');
+				write_char(':');
+				write_char(' ');
+
+				print_byte(SFR_DATA_24);
+				print_byte(SFR_DATA_16);
+				print_byte(SFR_DATA_8);
+				print_byte(SFR_DATA_0);
+				write_char(' ');
+			}
+		}
 	}
 }
 

From 8e9cababfb8cddf5ee5eec12cf0f17bf50e45cbf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20van=20Dorst?= <opensource@vdorst.com>
Date: Fri, 5 Sep 2025 00:10:18 +0200
Subject: [PATCH 02/12] gpio: show also bit changes vs last gpio cmd

---
 cmd_parser.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/cmd_parser.c b/cmd_parser.c
index 92d317a..ef06898 100644
--- a/cmd_parser.c
+++ b/cmd_parser.c
@@ -32,6 +32,7 @@ extern __code uint8_t * __code hex;
 extern __xdata uint8_t flash_buf[256];
 __xdata uint8_t vlan_names[VLAN_NAMES_SIZE];
 __xdata uint16_t vlan_ptr;
+__xdata uint8_t gpio_last_value[12] = { 0 };
 
 
 // Buffer for writing to flash 0x1fd000, copy to 0x1fe000
@@ -427,7 +428,7 @@ void cmd_parser(void) __banked
 
 		if (cmd_compare(0, "gpio")) {
 			for (uint8_t idx = 0; idx < 3; idx++) {
-				reg_read_m(RTL837X_REG_GPIO_A + (idx * 4));
+				reg_read(RTL837X_REG_GPIO_A + (idx * 4));
 				print_string("GPIO ");
 				write_char(idx + 'A');
 				write_char(':');
@@ -438,12 +439,20 @@ void cmd_parser(void) __banked
 				print_byte(SFR_DATA_8);
 				print_byte(SFR_DATA_0);
 				write_char(' ');
+				print_byte( gpio_last_value[(idx *4)] ^ SFR_DATA_24);
+				gpio_last_value[(idx *4)] = SFR_DATA_24;
+				print_byte( gpio_last_value[(idx *4) + 1] ^ SFR_DATA_16);
+				gpio_last_value[(idx *4) + 1] = SFR_DATA_16;
+				print_byte( gpio_last_value[(idx *4) + 2] ^ SFR_DATA_8);
+				gpio_last_value[(idx *4) + 2] = SFR_DATA_8;				 
+				print_byte( gpio_last_value[(idx *4) + 3] ^ SFR_DATA_0);
+				gpio_last_value[(idx *4) + 3] = SFR_DATA_0;	
+				write_char('\n');
 			}
 		}
 	}
 }
 
-
 void execute_config(void) __banked
 {
 	__xdata uint32_t pos = CONFIG_START;

From 74b8280d800b285bb9f2ff4b4080fea49fc104ef Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20van=20Dorst?= <opensource@vdorst.com>
Date: Sat, 6 Sep 2025 16:56:54 +0200
Subject: [PATCH 03/12] gpio: SOC only has 64 gpio not 96.

Remove BANK_A
Rename BANK_B to GPIO_00_31
Rename BACK_C to GPIO_32_63

Added also _INPUT, _DIRECTIOn registers
---
 cmd_parser.c    |  2 +-
 rtl837x_port.c  |  4 ++--
 rtl837x_regs.h  | 17 +++++++++++------
 rtlplayground.c | 36 ++++++++++++++++++------------------
 4 files changed, 32 insertions(+), 27 deletions(-)

diff --git a/cmd_parser.c b/cmd_parser.c
index ef06898..a7d03d7 100644
--- a/cmd_parser.c
+++ b/cmd_parser.c
@@ -428,7 +428,7 @@ void cmd_parser(void) __banked
 
 		if (cmd_compare(0, "gpio")) {
 			for (uint8_t idx = 0; idx < 3; idx++) {
-				reg_read(RTL837X_REG_GPIO_A + (idx * 4));
+				reg_read(RTL837X_REG_GPIO_32_63_OUTPUT + (idx * 4));
 				print_string("GPIO ");
 				write_char(idx + 'A');
 				write_char(':');
diff --git a/rtl837x_port.c b/rtl837x_port.c
index f999196..4383bf0 100644
--- a/rtl837x_port.c
+++ b/rtl837x_port.c
@@ -423,13 +423,13 @@ void port_stats_print(void) __banked
 				break;
 			}
 		} else {  // An SFP Module TODO: This is for 1 module devices
-			reg_read_m(RTL837X_REG_GPIO_B);
+			reg_read_m(RTL837X_REG_GPIO_00_31_INPUT);
 			if (!(sfr_data[0] & 0x40)) {
 				print_string("SFP OK\t");
 			} else {
 				print_string("NO SFP\t");
 			}
-			reg_read_m(RTL837X_REG_GPIO_C);
+			reg_read_m(RTL837X_REG_GPIO_32_63_INPUT);
 			if (sfr_data[3] & 0x20) {
 				print_string("Down\t");
 			} else {
diff --git a/rtl837x_regs.h b/rtl837x_regs.h
index a07f2be..58b09b7 100644
--- a/rtl837x_regs.h
+++ b/rtl837x_regs.h
@@ -44,19 +44,24 @@
  * Pin configuration (pinmux)
  */
 
-#define RTL837X_PIN_MUX_A	0x7f8c
-#define RTL837X_PIN_MUX_B	0x7f90
+#define RTL837X_PIN_MUX_0	0x7f8c
+#define RTL837X_PIN_MUX_1	0x7f90
 
-#define RTL837X_REG_GPIO_A 0x40
+// Output Registers
+#define RTL837X_REG_GPIO_00_31_OUTPUT 0x3c
+#define RTL837X_REG_GPIO_32_63_OUTPUT 0x40
 // BIT 4 resets RTL8224 on 9000-9XH
 
-#define RTL837X_REG_GPIO_B 0x44
+// Input Registers
+#define RTL837X_REG_GPIO_00_31_INPUT 0x44
+#define RTL837X_REG_GPIO_32_63_INPUT 0x48
 // Bit 1e cleared: SFP Module inserted on 9000-6XH (MOD_DEF0 pin)
 
-#define RTL837X_REG_GPIO_C 0x48
 // BIT 5 set: SIGNAL LOS of SFP module on 9000-6XH (RX_LOS pin)
 
-#define RTL837X_REG_GPIO_CONF_A 0x50
+// Direction Registers, 0 = input, 1 = output
+#define RTL837X_REG_GPIO_00_31_DIRECTION 0x4c
+#define RTL837X_REG_GPIO_32_63_DIRECTION 0x50
 // Configures IO direction for bank a
 
 #define RTL837X_REG_GPIO_EXT 0x63e8
diff --git a/rtlplayground.c b/rtlplayground.c
index c140362..dcff1f9 100644
--- a/rtlplayground.c
+++ b/rtlplayground.c
@@ -873,7 +873,7 @@ void sfp_print_info(uint8_t sfp)
 
 void handle_sfp(void)
 {
-	reg_read_m(RTL837X_REG_GPIO_B);
+	reg_read_m(RTL837X_REG_GPIO_00_31_INPUT);
 	if ((sfp_pins_last & 0x1) && (!(sfr_data[0] & 0x40))) {
 		sfp_pins_last &= ~0x01;
 		print_string("\n<MODULE INSERTED>  ");
@@ -893,7 +893,7 @@ void handle_sfp(void)
 		print_string("\n<MODULE REMOVED>\n");
 	}
 
-	reg_read_m(RTL837X_REG_GPIO_C);
+	reg_read_m(RTL837X_REG_GPIO_32_63_INPUT);
 	if ((sfp_pins_last & 0x2) && (!(sfr_data[3] & 0x20))) {
 		sfp_pins_last &= ~0x02;
 		print_string("\n<SFP-RX OK>\n");
@@ -903,7 +903,7 @@ void handle_sfp(void)
 		print_string("\n<SFP-RX LOS>\n");
 	}
 
-	reg_read_m(RTL837X_REG_GPIO_C);
+	reg_read_m(RTL837X_REG_GPIO_32_63_INPUT);
 	if ((sfp_pins_last & 0x10) && (!(sfr_data[1] & 0x04))) {
 		sfp_pins_last &= ~0x10;
 		print_string("\n<MODULE 2 INSERTED>  ");
@@ -989,7 +989,7 @@ void idle(void)
 	handle_sfp();
 
 	/* Button pressed on KL-8xhm-x2:
-	reg_read(RTL837X_REG_GPIO_C);
+	reg_read(RTL837X_REG_GPIO_32_63_INPUT);
 	if (!(sfr_data[2] & 0x40))
 		print_string("Button pressed\n");
 	*/
@@ -1038,12 +1038,12 @@ void setup_external_irqs(void)
 void rtl8224_enable(void)
 {
 	// Set Pin 4 low
-	reg_bit_clear(RTL837X_REG_GPIO_A, 4);
+	reg_bit_clear(RTL837X_REG_GPIO_32_63_OUTPUT, 4);
 	// Configure Pin as output
-	reg_bit_set(RTL837X_REG_GPIO_CONF_A, 4);
+	reg_bit_set(RTL837X_REG_GPIO_32_63_DIRECTION, 4);
 	delay(100);
 	// Set pin 4 high
-	reg_bit_set(RTL837X_REG_GPIO_A, 4);
+	reg_bit_set(RTL837X_REG_GPIO_32_63_OUTPUT, 4);
 	delay(500);
 }
 
@@ -1064,9 +1064,9 @@ void setup_clock(void)
 	reg_write_m(RTL837X_REG_HW_CONF);
 
 	// Enable serial interface, set bit 0
-	reg_read_m(RTL837X_PIN_MUX_B);
+	reg_read_m(RTL837X_PIN_MUX_1);
 	sfr_mask_data(0, 0x1, 0x1);
-	reg_write_m(RTL837X_PIN_MUX_B);
+	reg_write_m(RTL837X_PIN_MUX_1);
 }
 
 
@@ -1286,7 +1286,7 @@ void led_config_9xh(void)
 	reg_bit_clear(0x65dc, 0x1b);
 
 	// r7f8c:30000000 R7f8c-30000000 r7f8c:30000000 R7f8c-38000000
-	reg_bit_set(RTL837X_PIN_MUX_A, 0x1b);
+	reg_bit_set(RTL837X_PIN_MUX_0, 0x1b);
 
 	// R6548-0041017f
 	REG_SET(0x6548, 0x0041017f);
@@ -1338,13 +1338,13 @@ void led_config(void)
 
 	// Set bits 1b/1d of 0x7f8c: r7f8c:30000000 R7f8c-30000000 r7f8c:30000000 R7f8c-38000000
 	if (nSFPPorts == 2) {
-		reg_bit_set(RTL837X_PIN_MUX_A, 0x1b); // R7f8c-28000000
-		reg_bit_clear(RTL837X_PIN_MUX_A, 0x1c); // R7f8c-28000000
-		reg_bit_set(RTL837X_PIN_MUX_A, 0x1d); // R7f8c-28000000
+		reg_bit_set(RTL837X_PIN_MUX_0, 0x1b); // R7f8c-28000000
+		reg_bit_clear(RTL837X_PIN_MUX_0, 0x1c); // R7f8c-28000000
+		reg_bit_set(RTL837X_PIN_MUX_0, 0x1d); // R7f8c-28000000
 	} else {
-		reg_bit_set(RTL837X_PIN_MUX_A, 0x1d);
-		reg_bit_set(RTL837X_PIN_MUX_A, 0x1c);
-		reg_bit_set(RTL837X_PIN_MUX_A, 0x1b);
+		reg_bit_set(RTL837X_PIN_MUX_0, 0x1d);
+		reg_bit_set(RTL837X_PIN_MUX_0, 0x1c);
+		reg_bit_set(RTL837X_PIN_MUX_0, 0x1b);
 	}
 	// LED setup
 	// r6520:0021fdb0 R6520-0021e7b0 r6520:0021e7b0 R6520-0021e6b0 r65f8:00000018 R65f8-00000018 R65fc-fffff000 r6600:00000000 R6600-0000000f r65dc:5fffff00 R65dc-7fffff00 r65dc:7fffff00 R65dc-77ffff00
@@ -1620,10 +1620,10 @@ void setup_i2c(void)
 	REG_SET(0x041c, 0);
 
 	// HW Control register, enable I2C?
-	reg_read_m(RTL837X_PIN_MUX_B);
+	reg_read_m(RTL837X_PIN_MUX_1);
 	sfr_mask_data(3, 0x20, 0x00); // Clear bit 29
 	sfr_mask_data(0, 0x60, 0x40); // Set bits 5-6 to 0b10
-	reg_write_m(RTL837X_PIN_MUX_B);
+	reg_write_m(RTL837X_PIN_MUX_1);
 }
 
 

From e0864f811fdd151e140407547c4132dbf04a492f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20van=20Dorst?= <opensource@vdorst.com>
Date: Sat, 6 Sep 2025 17:05:16 +0200
Subject: [PATCH 04/12] cmd: move gpio status to a function print_gpio_status()

---
 cmd_parser.c | 55 +++++++++++++++++++++++++++++-----------------------
 1 file changed, 31 insertions(+), 24 deletions(-)

diff --git a/cmd_parser.c b/cmd_parser.c
index a7d03d7..c6bdbbd 100644
--- a/cmd_parser.c
+++ b/cmd_parser.c
@@ -32,7 +32,7 @@ extern __code uint8_t * __code hex;
 extern __xdata uint8_t flash_buf[256];
 __xdata uint8_t vlan_names[VLAN_NAMES_SIZE];
 __xdata uint16_t vlan_ptr;
-__xdata uint8_t gpio_last_value[12] = { 0 };
+__xdata uint8_t gpio_last_value[8] = { 0 };
 
 
 // Buffer for writing to flash 0x1fd000, copy to 0x1fe000
@@ -284,6 +284,34 @@ uint8_t cmd_tokenize(void) __banked
 	return 0;
 }
 
+// Print GPIO status
+void print_gpio_status(void) {
+	for (uint8_t idx = 0; idx < 2; idx++) {
+		reg_read(RTL837X_REG_GPIO_00_31_INPUT + (idx * 4));
+		print_string("GPIO ");
+		write_char(idx + '0');
+		write_char(':');
+		write_char(' ');
+
+		print_byte(SFR_DATA_24);
+		print_byte(SFR_DATA_16);
+		print_byte(SFR_DATA_8);
+		print_byte(SFR_DATA_0);
+
+		write_char(' ');
+		print_byte( gpio_last_value[(idx *4)] ^ SFR_DATA_24);
+		gpio_last_value[(idx *4)] = SFR_DATA_24;
+		print_byte( gpio_last_value[(idx *4) + 1] ^ SFR_DATA_16);
+		gpio_last_value[(idx *4) + 1] = SFR_DATA_16;
+		print_byte( gpio_last_value[(idx *4) + 2] ^ SFR_DATA_8);
+		gpio_last_value[(idx *4) + 2] = SFR_DATA_8;
+		print_byte( gpio_last_value[(idx *4) + 3] ^ SFR_DATA_0);
+		gpio_last_value[(idx *4) + 3] = SFR_DATA_0;
+		write_char('\n');
+		write_char('\n');
+	}
+}
+
 
 // Identify command
 void cmd_parser(void) __banked
@@ -426,29 +454,8 @@ void cmd_parser(void) __banked
 			print_reg(RTL837X_REG_SDS_MODES);
 		}
 
-		if (cmd_compare(0, "gpio")) {
-			for (uint8_t idx = 0; idx < 3; idx++) {
-				reg_read(RTL837X_REG_GPIO_32_63_OUTPUT + (idx * 4));
-				print_string("GPIO ");
-				write_char(idx + 'A');
-				write_char(':');
-				write_char(' ');
-
-				print_byte(SFR_DATA_24);
-				print_byte(SFR_DATA_16);
-				print_byte(SFR_DATA_8);
-				print_byte(SFR_DATA_0);
-				write_char(' ');
-				print_byte( gpio_last_value[(idx *4)] ^ SFR_DATA_24);
-				gpio_last_value[(idx *4)] = SFR_DATA_24;
-				print_byte( gpio_last_value[(idx *4) + 1] ^ SFR_DATA_16);
-				gpio_last_value[(idx *4) + 1] = SFR_DATA_16;
-				print_byte( gpio_last_value[(idx *4) + 2] ^ SFR_DATA_8);
-				gpio_last_value[(idx *4) + 2] = SFR_DATA_8;				 
-				print_byte( gpio_last_value[(idx *4) + 3] ^ SFR_DATA_0);
-				gpio_last_value[(idx *4) + 3] = SFR_DATA_0;	
-				write_char('\n');
-			}
+		if (cmd_compare(0, "gpio stat")) {
+			print_gpio_status();
 		}
 	}
 }

From 7e729c626cfaa84f7b30042db102c2bcd32285fe Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20van=20Dorst?= <opensource@vdorst.com>
Date: Sun, 7 Sep 2025 01:03:15 +0200
Subject: [PATCH 05/12] cmd: add reg read and write.

like:
* `reg w 04`
* `reg w 04 00023678`
---
 cmd_parser.c      | 133 ++++++++++++++++++++++++++++++++++++++++++++--
 rtl837x_common.h  |   1 +
 rtlplayground.c   |  11 ++++
 rtlplayground.mem |   4 +-
 4 files changed, 144 insertions(+), 5 deletions(-)

diff --git a/cmd_parser.c b/cmd_parser.c
index c6bdbbd..ed714e0 100644
--- a/cmd_parser.c
+++ b/cmd_parser.c
@@ -25,6 +25,7 @@ extern __xdata uint8_t isRTL8373;
 extern __xdata uint16_t mpos;
 
 extern volatile __xdata uint32_t ticks;
+extern volatile __xdata uint8_t sfr_data[4];
 
 extern __code uint8_t * __code greeting;
 extern __code uint8_t * __code hex;
@@ -34,6 +35,10 @@ __xdata uint8_t vlan_names[VLAN_NAMES_SIZE];
 __xdata uint16_t vlan_ptr;
 __xdata uint8_t gpio_last_value[8] = { 0 };
 
+// Temporatly for str to hex convertion value.
+// Support up to 32_bits.
+__xdata uint8_t hexvalue[4] = { 0 };
+
 
 // Buffer for writing to flash 0x1fd000, copy to 0x1fe000
 __xdata uint8_t cmd_buffer[SBUF_SIZE];
@@ -80,6 +85,50 @@ uint8_t cmd_compare(uint8_t start, uint8_t * __code cmd)
 }
 
 
+/* Converts ascii-hex array into value.
+	returns number of hexvalue[] entries has been written.
+	return value = 0 means error.
+*/
+uint8_t atoi_hex(uint8_t idx)
+{
+	uint8_t h_idx = 0;
+	uint8_t val = 0;
+	uint8_t c;
+
+	while(1) {
+		c = cmd_buffer[idx];
+
+		if (c == '\0' || c == ' ') {
+			break;
+		}
+
+		// swap hex nibbles
+		val = (val >> 4) | (val << 4);
+
+		if (c - '0' < 10) {
+			val |= c - '0';
+		} else {
+			c |= 0x20;
+			c -= 'a';
+			if (c > 5) {
+				h_idx = 0;
+				break;
+			}
+			val |= c + 10;
+		}
+
+		idx++;
+		hexvalue[h_idx >> 1] = val;
+
+		if (h_idx & 1 == 1) {
+			val = 0;
+		}
+		h_idx++;
+	}
+
+	return ((h_idx + 1) >> 1);
+}
+
 uint8_t atoi_short(register uint16_t *vlan, register uint8_t idx)
 {
 	uint8_t err = 1;
@@ -251,6 +300,82 @@ void parse_mirror(void)
 }
 
 
+void parse_reg(void)
+{
+	__xdata uint16_t reg = 0;
+	uint8_t read = 0xFF;
+
+	if (cmd_words_b[2] < 0) {
+		write_char('v');
+		goto err;
+	}
+
+	if (cmd_buffer[cmd_words_b[1]] == 'w') {
+		write_char('w');
+		read = 0;
+	}
+
+	if (cmd_buffer[cmd_words_b[1]] == 'r') {
+		write_char('r');
+		read = 1;
+	}
+
+	if (read == 0xFF) {
+		print_string("usage: reg r <hexvalue> or reg w <hexvalue> <hexvalue>");
+		return;
+	}
+
+	uint8_t hex_size = atoi_hex(cmd_words_b[2]);
+
+	if (hex_size == 0 || hex_size > 2) {
+		write_char('s');
+		goto err;
+	}
+
+	if (hex_size == 1) {
+		reg = hexvalue[0];
+	} else {
+		reg = (((uint16_t)hexvalue[0]) << 8) | hexvalue[1];
+	}
+
+	print_string("REG: ");
+	print_short(reg);
+	print_string(": VAL: ");
+
+	if (read) {
+		reg_read_m(reg);
+
+	} else {
+		hex_size = atoi_hex(cmd_words_b[3]);
+
+		if (hex_size == 0 || hex_size > 4 || cmd_words_b[3] < 0) {
+			write_char('S');
+			goto err_write;
+		}
+
+		// zero sfp data
+		sfr_set_zero();
+
+		// copy data over
+		while(hex_size) {
+			hex_size -= 1;
+			sfr_data[hex_size] = hexvalue[hex_size];
+		}
+
+		reg_write_m(reg);
+	}
+	print_sfr_data();
+	write_char('\n');
+	return;
+
+err:
+	print_string("usage: reg r <hexvalue> like reg r 00BB");
+	return;
+err_write:
+	print_string("usage: reg w <hexvalue> <hexvalue> like reg e 00BB 00112233");
+}
+
+
 // Parse command into words
 uint8_t cmd_tokenize(void) __banked
 {
@@ -308,7 +433,6 @@ void print_gpio_status(void) {
 		print_byte( gpio_last_value[(idx *4) + 3] ^ SFR_DATA_0);
 		gpio_last_value[(idx *4) + 3] = SFR_DATA_0;
 		write_char('\n');
-		write_char('\n');
 	}
 }
 
@@ -453,10 +577,12 @@ void cmd_parser(void) __banked
 		if (cmd_compare(0, "sds")) {
 			print_reg(RTL837X_REG_SDS_MODES);
 		}
-
-		if (cmd_compare(0, "gpio stat")) {
+		if (cmd_compare(0, "gpio")) {
 			print_gpio_status();
 		}
+		if (cmd_compare(0, "reg")) {
+			parse_reg();
+		}
 	}
 }
 
@@ -478,3 +604,4 @@ void execute_config(void) __banked
 		}
 	} while (mpos != 0xffff);
 }
+
diff --git a/rtl837x_common.h b/rtl837x_common.h
index 46f480d..35d1e49 100644
--- a/rtl837x_common.h
+++ b/rtl837x_common.h
@@ -75,6 +75,7 @@ void print_reg(uint16_t reg);
 uint8_t sfp_read_reg(uint8_t slot, uint8_t reg);
 void reg_bit_set(uint16_t reg_addr, char bit);
 void reg_bit_clear(uint16_t reg_addr, char bit);
+void sfr_set_zero(void);
 void reset_chip(void);
 void memcpy(__xdata void * __xdata dst, __xdata const void * __xdata src, uint16_t len);
 void memcpyc(register __xdata uint8_t *dst, register __code uint8_t *src, register uint16_t len);
diff --git a/rtlplayground.c b/rtlplayground.c
index dcff1f9..b5ea978 100644
--- a/rtlplayground.c
+++ b/rtlplayground.c
@@ -61,6 +61,7 @@ __xdata uint8_t sbuf[SBUF_SIZE];
 __xdata uint8_t sfr_data[4];
 
 extern __xdata uint8_t cmd_buffer[SBUF_SIZE];
+extern __xdata uint8_t gpio_last_value[8];
 
 __code uint8_t * __code greeting = "\nA minimal prompt to explore the RTL8372:\n";
 __code uint8_t * __code hex = "0123456789abcdef";
@@ -380,6 +381,16 @@ void sfr_mask_data(uint8_t n, uint8_t mask, uint8_t set)
 	sfr_data[3-n] = b;
 }
 
+/*
+ * This zeros all the sfr data fields
+ */
+void sfr_set_zero(void) {
+	uint8_t idx = 4;
+	while (idx) {
+		idx -= 1;
+		sfr_data[idx] = 0;
+	}
+}
 
 /*
  * Transfer Network Interface RX data from the ASIC to the 8051 XMEM
diff --git a/rtlplayground.mem b/rtlplayground.mem
index 5b1efa1..0f2fcb3 100644
--- a/rtlplayground.mem
+++ b/rtlplayground.mem
@@ -25,5 +25,5 @@ Other memory:
    Name             Start    End      Size     Max     
    ---------------- -------- -------- -------- --------
    PAGED EXT. RAM                         0      256   
-   EXTERNAL RAM     0x0001   0x1ad8    6872    16777216
-   ROM/EPROM/FLASH  0x0000   0x1c195  45278    16777216
+   EXTERNAL RAM     0x0001   0x1aea    6890    16777216
+   ROM/EPROM/FLASH  0x0000   0x1c72c  47034    16777216

From 074c89cf27dc2c7aa1d3003d3b54ce7a8cd95116 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20van=20Dorst?= <opensource@vdorst.com>
Date: Sun, 7 Sep 2025 14:50:50 +0200
Subject: [PATCH 06/12] cmd: convert reg to regget and regset.

We want to stick close to the origonal commands.
See: https://github.com/up-n-atom/SWTG118AS?tab=readme-ov-file#commands
---
 cmd_parser.c      | 104 +++++++++++++++++++++++++---------------------
 rtlplayground.mem |   4 +-
 2 files changed, 58 insertions(+), 50 deletions(-)

diff --git a/cmd_parser.c b/cmd_parser.c
index ed714e0..69e7dec 100644
--- a/cmd_parser.c
+++ b/cmd_parser.c
@@ -300,35 +300,18 @@ void parse_mirror(void)
 }
 
 
-void parse_reg(void)
+void parse_regget(void)
 {
-	__xdata uint16_t reg = 0;
-	uint8_t read = 0xFF;
+	uint16_t reg = 0;
 
 	if (cmd_words_b[2] < 0) {
 		write_char('v');
 		goto err;
 	}
 
-	if (cmd_buffer[cmd_words_b[1]] == 'w') {
-		write_char('w');
-		read = 0;
-	}
-
-	if (cmd_buffer[cmd_words_b[1]] == 'r') {
-		write_char('r');
-		read = 1;
-	}
-
-	if (read == 0xFF) {
-		print_string("usage: reg r <hexvalue> or reg w <hexvalue> <hexvalue>");
-		return;
-	}
-
-	uint8_t hex_size = atoi_hex(cmd_words_b[2]);
+	uint8_t hex_size = atoi_hex(cmd_words_b[1]);
 
 	if (hex_size == 0 || hex_size > 2) {
-		write_char('s');
 		goto err;
 	}
 
@@ -338,41 +321,63 @@ void parse_reg(void)
 		reg = (((uint16_t)hexvalue[0]) << 8) | hexvalue[1];
 	}
 
-	print_string("REG: ");
+	print_string("REGGET: ");
 	print_short(reg);
 	print_string(": VAL: ");
 
-	if (read) {
-		reg_read_m(reg);
-
-	} else {
-		hex_size = atoi_hex(cmd_words_b[3]);
-
-		if (hex_size == 0 || hex_size > 4 || cmd_words_b[3] < 0) {
-			write_char('S');
-			goto err_write;
-		}
-
-		// zero sfp data
-		sfr_set_zero();
-
-		// copy data over
-		while(hex_size) {
-			hex_size -= 1;
-			sfr_data[hex_size] = hexvalue[hex_size];
-		}
-
-		reg_write_m(reg);
-	}
+	reg_read_m(reg);
 	print_sfr_data();
 	write_char('\n');
 	return;
 
 err:
-	print_string("usage: reg r <hexvalue> like reg r 00BB");
+	print_string("usage: regget <hexvalue>\n\tlike: regget 0BB0 or regget 0c");
 	return;
-err_write:
-	print_string("usage: reg w <hexvalue> <hexvalue> like reg e 00BB 00112233");
+}
+
+
+void parse_regset(void)
+{
+	uint16_t reg = 0;
+
+	uint8_t hex_size = atoi_hex(cmd_words_b[1]);
+
+	if (hex_size == 0 || hex_size > 2) {
+		goto err;
+	}
+
+	if (hex_size == 1) {
+		reg = hexvalue[0];
+	} else {
+		reg = (((uint16_t)hexvalue[0]) << 8) | hexvalue[1];
+	}
+
+	hex_size = atoi_hex(cmd_words_b[2]);
+
+	if (hex_size == 0 || hex_size > 4 || cmd_words_b[3] < 0) {
+		goto err;
+	}
+
+	print_string("REGSET: ");
+	print_short(reg);
+	print_string(": VAL: ");
+
+	// zero sfp data
+	sfr_set_zero();
+
+	// copy data over
+	while(hex_size) {
+		hex_size -= 1;
+		sfr_data[hex_size] = hexvalue[hex_size];
+	}
+
+	reg_write_m(reg);
+	print_sfr_data();
+	write_char('\n');
+	return;
+
+err:
+	print_string("usage: regset <hexvalue> <hexvalue>\n\tlike regset 0b abcd1234.");
 }
 
 
@@ -580,8 +585,11 @@ void cmd_parser(void) __banked
 		if (cmd_compare(0, "gpio")) {
 			print_gpio_status();
 		}
-		if (cmd_compare(0, "reg")) {
-			parse_reg();
+		if (cmd_compare(0, "regget")) {
+			parse_regget();
+		}
+		if (cmd_compare(0, "regset")) {
+			parse_regset();
 		}
 	}
 }
diff --git a/rtlplayground.mem b/rtlplayground.mem
index 0f2fcb3..ab1078f 100644
--- a/rtlplayground.mem
+++ b/rtlplayground.mem
@@ -25,5 +25,5 @@ Other memory:
    Name             Start    End      Size     Max     
    ---------------- -------- -------- -------- --------
    PAGED EXT. RAM                         0      256   
-   EXTERNAL RAM     0x0001   0x1aea    6890    16777216
-   ROM/EPROM/FLASH  0x0000   0x1c72c  47034    16777216
+   EXTERNAL RAM     0x0001   0x1ae8    6888    16777216
+   ROM/EPROM/FLASH  0x0000   0x1c72d  47021    16777216

From 1b578405c003bfbbb382c375244e8e02226ef3b0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20van=20Dorst?= <opensource@vdorst.com>
Date: Sun, 7 Sep 2025 14:56:13 +0200
Subject: [PATCH 07/12] Remove unused and not related to GPIO define

---
 rtl837x_regs.h | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/rtl837x_regs.h b/rtl837x_regs.h
index 58b09b7..326acb8 100644
--- a/rtl837x_regs.h
+++ b/rtl837x_regs.h
@@ -62,9 +62,6 @@
 // Direction Registers, 0 = input, 1 = output
 #define RTL837X_REG_GPIO_00_31_DIRECTION 0x4c
 #define RTL837X_REG_GPIO_32_63_DIRECTION 0x50
-// Configures IO direction for bank a
-
-#define RTL837X_REG_GPIO_EXT 0x63e8
 
 /*
  * I2C controller

From 4cad857ad5a3158de69ddb4113a852881292b180 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20van=20Dorst?= <opensource@vdorst.com>
Date: Sun, 7 Sep 2025 16:33:01 +0200
Subject: [PATCH 08/12] fix: cmd: regset: need add offset when we have less
 then 8 hex numbers

---
 cmd_parser.c      | 3 ++-
 rtlplayground.mem | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/cmd_parser.c b/cmd_parser.c
index 69e7dec..a45850e 100644
--- a/cmd_parser.c
+++ b/cmd_parser.c
@@ -365,10 +365,11 @@ void parse_regset(void)
 	// zero sfp data
 	sfr_set_zero();
 
+	uint8_t offset = 4 - hex_size;
 	// copy data over
 	while(hex_size) {
 		hex_size -= 1;
-		sfr_data[hex_size] = hexvalue[hex_size];
+		sfr_data[offset + hex_size] = hexvalue[hex_size];
 	}
 
 	reg_write_m(reg);
diff --git a/rtlplayground.mem b/rtlplayground.mem
index ab1078f..622a980 100644
--- a/rtlplayground.mem
+++ b/rtlplayground.mem
@@ -26,4 +26,4 @@ Other memory:
    ---------------- -------- -------- -------- --------
    PAGED EXT. RAM                         0      256   
    EXTERNAL RAM     0x0001   0x1ae8    6888    16777216
-   ROM/EPROM/FLASH  0x0000   0x1c72d  47021    16777216
+   ROM/EPROM/FLASH  0x0000   0x1c735  47029    16777216

From 54ab915557faa187f04fcfc424b35f1b484a4aee Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20van=20Dorst?= <opensource@vdorst.com>
Date: Sun, 7 Sep 2025 16:52:51 +0200
Subject: [PATCH 09/12] cmd: reg{get,set}: more small refactor

Refactor some value checking.
Simplified hexvalue to addr.
Updated some comments.
Remove extra debug prints and EOL after the command.
---
 cmd_parser.c      | 41 ++++++++++++++++++++---------------------
 rtlplayground.mem |  2 +-
 2 files changed, 21 insertions(+), 22 deletions(-)

diff --git a/cmd_parser.c b/cmd_parser.c
index a45850e..27eb596 100644
--- a/cmd_parser.c
+++ b/cmd_parser.c
@@ -304,8 +304,7 @@ void parse_regget(void)
 {
 	uint16_t reg = 0;
 
-	if (cmd_words_b[2] < 0) {
-		write_char('v');
+	if (cmd_words_b[1] < 0) {
 		goto err;
 	}
 
@@ -315,10 +314,10 @@ void parse_regget(void)
 		goto err;
 	}
 
-	if (hex_size == 1) {
-		reg = hexvalue[0];
-	} else {
-		reg = (((uint16_t)hexvalue[0]) << 8) | hexvalue[1];
+	reg = hexvalue[0];
+	if (hex_size == 2) {
+		reg <<= 8;
+		reg |= hexvalue[1];
 	}
 
 	print_string("REGGET: ");
@@ -327,7 +326,6 @@ void parse_regget(void)
 
 	reg_read_m(reg);
 	print_sfr_data();
-	write_char('\n');
 	return;
 
 err:
@@ -340,41 +338,42 @@ void parse_regset(void)
 {
 	uint16_t reg = 0;
 
-	uint8_t hex_size = atoi_hex(cmd_words_b[1]);
+	if (cmd_words_b[2] < 0) {
+		goto err;
+	}
 
+	uint8_t hex_size = atoi_hex(cmd_words_b[1]);
 	if (hex_size == 0 || hex_size > 2) {
 		goto err;
 	}
 
-	if (hex_size == 1) {
-		reg = hexvalue[0];
-	} else {
-		reg = (((uint16_t)hexvalue[0]) << 8) | hexvalue[1];
+	reg = hexvalue[0];
+	if (hex_size == 2) {
+		reg <<= 8;
+		reg |= hexvalue[1];
 	}
 
 	hex_size = atoi_hex(cmd_words_b[2]);
-
-	if (hex_size == 0 || hex_size > 4 || cmd_words_b[3] < 0) {
+	if (hex_size == 0 || hex_size > 4) {
 		goto err;
 	}
 
-	print_string("REGSET: ");
-	print_short(reg);
-	print_string(": VAL: ");
-
-	// zero sfp data
+	// zero sfr memory data
 	sfr_set_zero();
 
+	// copy data over sfr memory
 	uint8_t offset = 4 - hex_size;
-	// copy data over
 	while(hex_size) {
 		hex_size -= 1;
 		sfr_data[offset + hex_size] = hexvalue[hex_size];
 	}
+	print_string("REGSET: ");
+	print_short(reg);
 
 	reg_write_m(reg);
+
+	print_string(": VAL: ");
 	print_sfr_data();
-	write_char('\n');
 	return;
 
 err:
diff --git a/rtlplayground.mem b/rtlplayground.mem
index 622a980..7626c2d 100644
--- a/rtlplayground.mem
+++ b/rtlplayground.mem
@@ -26,4 +26,4 @@ Other memory:
    ---------------- -------- -------- -------- --------
    PAGED EXT. RAM                         0      256   
    EXTERNAL RAM     0x0001   0x1ae8    6888    16777216
-   ROM/EPROM/FLASH  0x0000   0x1c735  47029    16777216
+   ROM/EPROM/FLASH  0x0000   0x1c71b  47003    16777216

From bde84544493bf4ca72fe59eacaecc847a4e54db8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20van=20Dorst?= <opensource@vdorst.com>
Date: Sun, 7 Sep 2025 17:04:46 +0200
Subject: [PATCH 10/12] isletter(): optimized version

Less instructions and jumps.
Saves 39 bytes.

```patch
1634,1651c1621,1628
<       mov     r7,a
<       mov     r6,a
< ;     cmd_parser.c:63: return (l >= 'a' && l <= 'z') || (l >= 'A' && l <= 'Z');
<       cjne    r7,#0x61,00326$
< 00326$:
<       mov     _parse_vlan_sloc0_1_0,c
<       jc      00153$
<       mov     a,r7
<       add     a,#0xff - 0x7a
<       mov     _parse_vlan_sloc0_1_0,c
<       jnc     00149$
< 00153$:
<       cjne    r6,#0x41,00329$
< 00329$:
<       mov     _parse_vlan_sloc0_1_0,c
<       jc      00132$
<       mov     a,r6
<       add     a,#0xff - 0x5a
---
> ;     cmd_parser.c:66: l |= 0x20;
> ;     cmd_parser.c:67: l -= 'A';
>       orl     a,#0x20
> ;     cmd_parser.c:68: return (l <= ('Z'-'A'));
>       add     a,#0xbf
>       add     a,#0xff - 0x19
>       cpl     c
> ;     cmd_parser.c:245: if (cmd_words_b[2] > 0 && isletter(cmd_buffer[cmd_words_b[2]])) {
1653,1654c1630
<       jc      00132$
< 00149$:
---
>       jnc     00132$
```
---
 cmd_parser.c      | 7 ++++++-
 rtlplayground.mem | 2 +-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/cmd_parser.c b/cmd_parser.c
index 27eb596..bf09cdf 100644
--- a/cmd_parser.c
+++ b/cmd_parser.c
@@ -60,7 +60,12 @@ __code uint8_t phys_to_log_port[6] = {
 
 inline uint8_t isletter(uint8_t l)
 {
-	return (l >= 'a' && l <= 'z') || (l >= 'A' && l <= 'Z');
+	// return (l >= 'a' && l <= 'z') || (l >= 'A' && l <= 'Z');
+
+	// Make it upper case
+	l |= 0x20;
+	l -= 'A';
+	return (l <= ('Z'-'A'));
 }
 
 
diff --git a/rtlplayground.mem b/rtlplayground.mem
index 7626c2d..cc92f39 100644
--- a/rtlplayground.mem
+++ b/rtlplayground.mem
@@ -26,4 +26,4 @@ Other memory:
    ---------------- -------- -------- -------- --------
    PAGED EXT. RAM                         0      256   
    EXTERNAL RAM     0x0001   0x1ae8    6888    16777216
-   ROM/EPROM/FLASH  0x0000   0x1c71b  47003    16777216
+   ROM/EPROM/FLASH  0x0000   0x1c6f2  46962    16777216

From 7a2e568fccdf08e732b2385af5d96b4ac70c9b7f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20van=20Dorst?= <opensource@vdorst.com>
Date: Sun, 7 Sep 2025 17:18:36 +0200
Subject: [PATCH 11/12] Make a helper isnumber(), replace all same patterns.

---
 cmd_parser.c      | 27 +++++++++++++++++----------
 rtlplayground.mem |  2 +-
 2 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/cmd_parser.c b/cmd_parser.c
index bf09cdf..3eb4986 100644
--- a/cmd_parser.c
+++ b/cmd_parser.c
@@ -68,6 +68,13 @@ inline uint8_t isletter(uint8_t l)
 	return (l <= ('Z'-'A'));
 }
 
+inline uint8_t isnumber(uint8_t l)
+{
+	// return (l >= '0' && l <= '9');
+	l -= '0';
+	return (l <= ('9'-'0'));
+}
+
 
 uint8_t cmd_compare(uint8_t start, uint8_t * __code cmd)
 {
@@ -139,7 +146,7 @@ uint8_t atoi_short(register uint16_t *vlan, register uint8_t idx)
 	uint8_t err = 1;
 	*vlan = 0;
 
-	while (cmd_buffer[idx] >= '0' && cmd_buffer[idx] <= '9') {
+	while (isnumber(cmd_buffer[idx])) {
 		err = 0;
 		*vlan = (*vlan * 10) + cmd_buffer[idx] - '0';
 		idx++;
@@ -154,7 +161,7 @@ uint8_t parse_ip(register uint8_t idx)
 
 	for (b = 0; b < 4; b++) {
 		ip[b] = 0;
-		while (cmd_buffer[idx] >= '0' && cmd_buffer[idx] <= '9') {
+		while (isnumber(cmd_buffer[idx])) {
 			ip[b] = (ip[b] * 10) + cmd_buffer[idx] - '0';
 			idx++;
 		}
@@ -177,7 +184,7 @@ void parse_trunk(void)
 	uint8_t w = 2;
 	while (cmd_words_b[w] > 0) {
 		uint8_t port;
-		if (cmd_buffer[cmd_words_b[w]] >= '0' && cmd_buffer[cmd_words_b[w]] <= '9') {
+		if (isnumber(cmd_buffer[cmd_words_b[w]])) {
 			port = cmd_buffer[cmd_words_b[w]] - '1';
 			if (port > maxPort)
 				goto err;
@@ -222,9 +229,9 @@ void parse_vlan(void)
 		}
 		while (cmd_words_b[w] > 0) {
 			uint8_t port;
-			if (cmd_buffer[cmd_words_b[w]] >= '0' && cmd_buffer[cmd_words_b[w]] <= '9') {
+			if (isnumber(cmd_buffer[cmd_words_b[w]])) {
 				port = cmd_buffer[cmd_words_b[w]] - '1';
-				if (cmd_buffer[cmd_words_b[w] + 1] >= '0' && cmd_buffer[cmd_words_b[w] + 1] <= '9') {
+				if (isnumber(cmd_buffer[cmd_words_b[w] + 1])) {
 					port = (port + 1) * 10 + cmd_buffer[cmd_words_b[w] + 1] - '1';
 					if (cmd_buffer[cmd_words_b[w] + 2] == 't')
 						tagged |= ((uint16_t)1) << port;
@@ -258,23 +265,23 @@ void parse_mirror(void)
 	__xdata uint16_t rx_pmask = 0;
 	__xdata uint16_t tx_pmask = 0;
 
-	if (cmd_buffer[cmd_words_b[1]] < '0' || cmd_buffer[cmd_words_b[1]] > '9') {
+	if (!isnumber(cmd_buffer[cmd_words_b[1]])) {
 		print_string("Port missing: port <mirroring port> [port][t/r]...");
 		return;
 	}
 
 	mirroring_port = cmd_buffer[cmd_words_b[1]] - '1';
-	if (cmd_buffer[cmd_words_b[1] + 1] >= '0' && cmd_buffer[cmd_words_b[1] + 1] <= '9')
-	mirroring_port = (mirroring_port + 1) * 10 + cmd_buffer[cmd_words_b[1] + 1] - '1';
+	if (isnumber(cmd_buffer[cmd_words_b[1] + 1]))
+		mirroring_port = (mirroring_port + 1) * 10 + cmd_buffer[cmd_words_b[1] + 1] - '1';
 	if (!isRTL8373)
 		mirroring_port = phys_to_log_port[mirroring_port];
 
 	uint8_t w = 2;
 	while (cmd_words_b[w] > 0) {
 		uint8_t port;
-		if (cmd_buffer[cmd_words_b[w]] >= '0' && cmd_buffer[cmd_words_b[w]] <= '9') {
+		if (isnumber(cmd_buffer[cmd_words_b[w]])) {
 			port = cmd_buffer[cmd_words_b[w]] - '1';
-			if (cmd_buffer[cmd_words_b[w] + 1] >= '0' && cmd_buffer[cmd_words_b[w] + 1] <= '9') {
+			if (isnumber(cmd_buffer[cmd_words_b[w] + 1])) {
 				port = (port + 1) * 10 + cmd_buffer[cmd_words_b[w] + 1] - '1';
 				if (!isRTL8373)
 					port = phys_to_log_port[port];
diff --git a/rtlplayground.mem b/rtlplayground.mem
index cc92f39..0259cd7 100644
--- a/rtlplayground.mem
+++ b/rtlplayground.mem
@@ -26,4 +26,4 @@ Other memory:
    ---------------- -------- -------- -------- --------
    PAGED EXT. RAM                         0      256   
    EXTERNAL RAM     0x0001   0x1ae8    6888    16777216
-   ROM/EPROM/FLASH  0x0000   0x1c6f2  46962    16777216
+   ROM/EPROM/FLASH  0x0000   0x1c69f  46879    16777216

From 455d2e28d6487e63919e221a425b130c65d7f9b6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20van=20Dorst?= <opensource@vdorst.com>
Date: Mon, 8 Sep 2025 18:50:48 +0200
Subject: [PATCH 12/12] fix: isletter(), make everything lowercase.

---
 cmd_parser.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/cmd_parser.c b/cmd_parser.c
index 3eb4986..f976fe2 100644
--- a/cmd_parser.c
+++ b/cmd_parser.c
@@ -62,12 +62,13 @@ inline uint8_t isletter(uint8_t l)
 {
 	// return (l >= 'a' && l <= 'z') || (l >= 'A' && l <= 'Z');
 
-	// Make it upper case
+	// Make it lowercase
 	l |= 0x20;
-	l -= 'A';
-	return (l <= ('Z'-'A'));
+	l -= 'a';
+	return (l <= ('z'-'a'));
 }
 
+
 inline uint8_t isnumber(uint8_t l)
 {
 	// return (l >= '0' && l <= '9');