From b3395184cc45708a19688dae58e03cfc000894ce Mon Sep 17 00:00:00 2001
From: deadprogram <ron@hybridgroup.com>
Date: Tue, 17 Mar 2026 12:33:49 +0100
Subject: [PATCH] machine/esp32xx: add WASM simulator support for
 ESP32-C3/ESP32-S3 targets

Signed-off-by: deadprogram <ron@hybridgroup.com>
---
 GNUmakefile                              |   2 +
 src/machine/machine_esp32xx_simulator.go | 134 +++++++++++++++++++++++
 2 files changed, 136 insertions(+)
 create mode 100644 src/machine/machine_esp32xx_simulator.go

diff --git a/GNUmakefile b/GNUmakefile
index 9a6dc7b8e5..d7587d5bb3 100644
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -644,6 +644,8 @@ ifneq ($(WASM), 0)
 	@$(MD5SUM) test.wasm
 	GOOS=js GOARCH=wasm $(TINYGO) build -size short -o test.wasm -tags=pico                 examples/blinky1
 	@$(MD5SUM) test.wasm
+	GOOS=js GOARCH=wasm $(TINYGO) build -size short -o test.wasm -tags=xiao_esp32s3         examples/blinky1
+	@$(MD5SUM) test.wasm
 endif
 	# test all targets/boards
 	$(TINYGO) build -size short -o test.hex -target=pca10040-s132v6     examples/blinky1
diff --git a/src/machine/machine_esp32xx_simulator.go b/src/machine/machine_esp32xx_simulator.go
new file mode 100644
index 0000000000..44de65690f
--- /dev/null
+++ b/src/machine/machine_esp32xx_simulator.go
@@ -0,0 +1,134 @@
+//go:build !baremetal && (xiao_esp32c3 || xiao_esp32s3)
+
+// Simulator support for ESP32-C3 and ESP32-S3 based boards.
+
+package machine
+
+// Hardware pin numbers
+const (
+	GPIO0  Pin = 0
+	GPIO1  Pin = 1
+	GPIO2  Pin = 2
+	GPIO3  Pin = 3
+	GPIO4  Pin = 4
+	GPIO5  Pin = 5
+	GPIO6  Pin = 6
+	GPIO7  Pin = 7
+	GPIO8  Pin = 8
+	GPIO9  Pin = 9
+	GPIO10 Pin = 10
+	GPIO11 Pin = 11
+	GPIO12 Pin = 12
+	GPIO13 Pin = 13
+	GPIO14 Pin = 14
+	GPIO15 Pin = 15
+	GPIO16 Pin = 16
+	GPIO17 Pin = 17
+	GPIO18 Pin = 18
+	GPIO19 Pin = 19
+	GPIO20 Pin = 20
+	GPIO21 Pin = 21
+	GPIO26 Pin = 26
+	GPIO27 Pin = 27
+	GPIO28 Pin = 28
+	GPIO29 Pin = 29
+	GPIO30 Pin = 30
+	GPIO31 Pin = 31
+	GPIO32 Pin = 32
+	GPIO33 Pin = 33
+	GPIO34 Pin = 34
+	GPIO35 Pin = 35
+	GPIO36 Pin = 36
+	GPIO37 Pin = 37
+	GPIO38 Pin = 38
+	GPIO39 Pin = 39
+	GPIO40 Pin = 40
+	GPIO41 Pin = 41
+	GPIO42 Pin = 42
+	GPIO43 Pin = 43
+	GPIO44 Pin = 44
+	GPIO45 Pin = 45
+	GPIO46 Pin = 46
+	GPIO47 Pin = 47
+	GPIO48 Pin = 48
+)
+
+const (
+	ADC0  Pin = GPIO1
+	ADC2  Pin = GPIO2
+	ADC3  Pin = GPIO3
+	ADC4  Pin = GPIO4
+	ADC5  Pin = GPIO5
+	ADC6  Pin = GPIO6
+	ADC7  Pin = GPIO7
+	ADC8  Pin = GPIO8
+	ADC9  Pin = GPIO9
+	ADC10 Pin = GPIO10
+	ADC11 Pin = GPIO11
+	ADC12 Pin = GPIO12
+	ADC13 Pin = GPIO13
+	ADC14 Pin = GPIO14
+	ADC15 Pin = GPIO15
+	ADC16 Pin = GPIO16
+	ADC17 Pin = GPIO17
+	ADC18 Pin = GPIO18
+	ADC19 Pin = GPIO19
+	ADC20 Pin = GPIO20
+)
+
+// Channel values below are nil, so that they get filled in on the first use.
+// This is the same as what happens on baremetal.
+
+var PWM0 = &timerType{
+	instance:   0,
+	frequency:  16e6,
+	bits:       15,
+	prescalers: []int{1, 2, 4, 8, 16, 32, 64, 128},
+	channelPins: [][]Pin{
+		nil, // channel 0
+		nil, // channel 1
+		nil, // channel 2
+		nil, // channel 3
+	},
+}
+
+var PWM1 = &timerType{
+	instance:   1,
+	frequency:  16e6,
+	bits:       15,
+	prescalers: []int{1, 2, 4, 8, 16, 32, 64, 128},
+	channelPins: [][]Pin{
+		nil, // channel 0
+		nil, // channel 1
+		nil, // channel 2
+		nil, // channel 3
+	},
+}
+
+var PWM2 = &timerType{
+	instance:   2,
+	frequency:  16e6,
+	bits:       15,
+	prescalers: []int{1, 2, 4, 8, 16, 32, 64, 128},
+	channelPins: [][]Pin{
+		nil, // channel 0
+		nil, // channel 1
+		nil, // channel 2
+		nil, // channel 3
+	},
+}
+
+var PWM3 = &timerType{
+	instance:   3,
+	frequency:  16e6,
+	bits:       15,
+	prescalers: []int{1, 2, 4, 8, 16, 32, 64, 128},
+	channelPins: [][]Pin{
+		nil, // channel 0
+		nil, // channel 1
+		nil, // channel 2
+		nil, // channel 3
+	},
+}
+
+var I2C0 = &I2C{Bus: 0}