diff --git a/rp2-pio/piolib/all_generate.go b/rp2-pio/piolib/all_generate.go
index b0a73f0..d5d8d5e 100644
--- a/rp2-pio/piolib/all_generate.go
+++ b/rp2-pio/piolib/all_generate.go
@@ -12,6 +12,8 @@ var errTimeout = errors.New("piolib:timeout")
 //go:generate pioasm -o go spi.pio        spi_pio.go
 //go:generate pioasm -o go ws2812.pio     ws2812_pio.go
 //go:generate pioasm -o go i2s.pio        i2s_pio.go
+//go:generate pioasm -o go sdio.pio       sdio_pio.go
+
 func gosched() {
 	runtime.Gosched()
 }
diff --git a/rp2-pio/piolib/sdio.go b/rp2-pio/piolib/sdio.go
new file mode 100644
index 0000000..486dd7b
--- /dev/null
+++ b/rp2-pio/piolib/sdio.go
@@ -0,0 +1,235 @@
+//go:build rp2040
+
+package piolib
+
+import (
+	"device/rp"
+
+	pio "github.com/tinygo-org/pio/rp2-pio"
+)
+
+const bw_wide = 4
+
+type SDIO struct {
+	pio                 *pio.PIO
+	smDat, smClk, smCmd uint8
+	progOffset          uint8 // Program offset.
+	sdMask              uint32
+	lenByte             uint16
+	busWidth            uint8
+}
+
+type SDIOConfig struct {
+}
+
+func NewSDIO(smDat, smClk pio.StateMachine, cfg SDIOConfig) (*SDIO, error) {
+	// sm.Claim() // SM should be claimed beforehand, we just guarantee it's claimed.
+	// Pio := smDat.PIO()
+	panic("NOT IMPLEMENTED")
+}
+
+func (sd *SDIO) startRead(smidx uint8, enable bool) error {
+	sm := sd.pio.StateMachine(smidx)
+	sd.assert()
+	bitLength := sd.lenByte * 8
+	if smidx == sd.smDat {
+		if sd.isWide() {
+			bitLength += 64
+		} else {
+			bitLength += 16
+		}
+	}
+	err := safeWaitTxNotFull(sm)
+	if err != nil {
+		return err
+	}
+	if sd.isWide() && smidx != sd.smCmd {
+		sm.TxPut(sd.pioCmd(sdCmdOrDatoffset_stateRxBits, uint16(bitLength)/4-1))
+		// Note -1 since wrap values are on the last instruction before wrap.
+		sm.SetWrap(sdCmdOrDatoffset_wrapTargetFor4bitRx, sdCmdOrDatoffset_wrapFor4bitRx-1)
+	} else {
+		sm.TxPut(sd.pioCmd(sdCmdOrDatoffset_stateRxBits, uint16(bitLength)-1))
+		sm.SetWrap(sdCmdOrDatWrapTarget, sdCmdOrDatWrap)
+	}
+	sd.deassert()
+	sd.assert()
+	if enable {
+		sm.SetEnabled(true)
+	}
+	if bitLength&31 != 0 {
+		err = safeWaitTxNotFull(sm)
+		if err != nil {
+			return err
+		}
+		sm.TxPut(sd.pioCmd(sdCmdOrDatoffset_stateInlineInstruction,
+			pio.EncodeIn(pio.SrcDestNull, 32-(bitLength&31))))
+	}
+	err = safeWaitTxNotFull(sm)
+	if err != nil {
+		return err
+	}
+
+	var instr uint16
+	if smidx == sd.smDat {
+		instr = sdCmdOrDatoffset_noArgStateWaitForCmdBits
+	} else {
+		instr = sdCmdOrDatoffset_noArgStateWaitHigh
+	}
+
+	sm.TxPut(sd.pioCmd(sdCmdOrDatoffset_noArgStateWaitForCmdBits, pio.EncodeJmp(instr)))
+	sd.deassert()
+	return nil
+}
+
+func (sd *SDIO) pioCmd(cmd, param uint16) uint32 {
+	if cmd <= uint16(len(sdCmdOrDatInstructions)) {
+		panic("sdio:bad cmd")
+	}
+	return uint32(pio.EncodeJmp(cmd))<<16 | uint32(param)
+}
+
+func (sd *SDIO) isWide() bool {
+	return sd.busWidth == bw_wide
+}
+
+func (sd *SDIO) assert() {
+	rp.SIO.GPIO_OUT_SET.Set(sd.sdMask)
+}
+func (sd *SDIO) deassert() {
+	rp.SIO.GPIO_OUT_CLR.Set(sd.sdMask)
+}
+
+const sdMaxWait = 1000000
+
+func safeWaitTxNotFull(sm pio.StateMachine) error {
+	wooble := 0
+	for sm.IsTxFIFOFull() {
+		wooble++
+		if wooble > sdMaxWait {
+			return errTimeout
+		}
+	}
+	return nil
+}
+
+func safeWaitTxEmpty(sm pio.StateMachine) error {
+	wooble := 0
+	for !sm.IsTxFIFOEmpty() {
+		wooble++
+		if wooble > sdMaxWait {
+			return errTimeout
+		}
+	}
+	return nil
+}
+
+func acquiesce(sm pio.StateMachine) error {
+	err := safeWaitTxEmpty(sm)
+	if err != nil {
+		return err
+	}
+	foo := 0
+	timeout := sdMaxWait
+	for timeout > 0 {
+		timeout--
+		addr := sm.HW().ADDR.Get()
+		foo |= 1 << addr
+		if addr == sdCmdOrDatoffset_noArgStateWaitForCmdBits {
+			break
+		}
+	}
+	if timeout <= 0 {
+		return errTimeout
+	}
+	return nil
+}
+
+func sdMakeCommand(cmd, b0, b1, b2, b3 uint8) (rc uint64) {
+	cmd |= 0x40
+
+	var crc uint8
+	crc = crc7Table[crc^cmd]
+	crc = crc7Table[crc^b0]
+	crc = crc7Table[crc^b1]
+	crc = crc7Table[crc^b2]
+	crc = crc7Table[crc^b3]
+
+	rc = uint64(b3)
+	rc = (rc << 8) | uint64(crc) | 1                      // crc and stop bit
+	rc = (rc << 16) | sdCmdOrDatoffset_noArgStateWaitHigh // wtf?
+	rc = (rc << 8) | uint64(cmd)
+	rc = (rc << 8) | uint64(b0)
+	rc = (rc << 8) | uint64(b1)
+	rc = (rc << 8) | uint64(b2)
+	return rc
+}
+
+var crc7Table = [256]uint8{
+	0x00, 0x12, 0x24, 0x36, 0x48, 0x5a, 0x6c, 0x7e,
+	0x90, 0x82, 0xb4, 0xa6, 0xd8, 0xca, 0xfc, 0xee,
+	0x32, 0x20, 0x16, 0x04, 0x7a, 0x68, 0x5e, 0x4c,
+	0xa2, 0xb0, 0x86, 0x94, 0xea, 0xf8, 0xce, 0xdc,
+	0x64, 0x76, 0x40, 0x52, 0x2c, 0x3e, 0x08, 0x1a,
+	0xf4, 0xe6, 0xd0, 0xc2, 0xbc, 0xae, 0x98, 0x8a,
+	0x56, 0x44, 0x72, 0x60, 0x1e, 0x0c, 0x3a, 0x28,
+	0xc6, 0xd4, 0xe2, 0xf0, 0x8e, 0x9c, 0xaa, 0xb8,
+	0xc8, 0xda, 0xec, 0xfe, 0x80, 0x92, 0xa4, 0xb6,
+	0x58, 0x4a, 0x7c, 0x6e, 0x10, 0x02, 0x34, 0x26,
+	0xfa, 0xe8, 0xde, 0xcc, 0xb2, 0xa0, 0x96, 0x84,
+	0x6a, 0x78, 0x4e, 0x5c, 0x22, 0x30, 0x06, 0x14,
+	0xac, 0xbe, 0x88, 0x9a, 0xe4, 0xf6, 0xc0, 0xd2,
+	0x3c, 0x2e, 0x18, 0x0a, 0x74, 0x66, 0x50, 0x42,
+	0x9e, 0x8c, 0xba, 0xa8, 0xd6, 0xc4, 0xf2, 0xe0,
+	0x0e, 0x1c, 0x2a, 0x38, 0x46, 0x54, 0x62, 0x70,
+	0x82, 0x90, 0xa6, 0xb4, 0xca, 0xd8, 0xee, 0xfc,
+	0x12, 0x00, 0x36, 0x24, 0x5a, 0x48, 0x7e, 0x6c,
+	0xb0, 0xa2, 0x94, 0x86, 0xf8, 0xea, 0xdc, 0xce,
+	0x20, 0x32, 0x04, 0x16, 0x68, 0x7a, 0x4c, 0x5e,
+	0xe6, 0xf4, 0xc2, 0xd0, 0xae, 0xbc, 0x8a, 0x98,
+	0x76, 0x64, 0x52, 0x40, 0x3e, 0x2c, 0x1a, 0x08,
+	0xd4, 0xc6, 0xf0, 0xe2, 0x9c, 0x8e, 0xb8, 0xaa,
+	0x44, 0x56, 0x60, 0x72, 0x0c, 0x1e, 0x28, 0x3a,
+	0x4a, 0x58, 0x6e, 0x7c, 0x02, 0x10, 0x26, 0x34,
+	0xda, 0xc8, 0xfe, 0xec, 0x92, 0x80, 0xb6, 0xa4,
+	0x78, 0x6a, 0x5c, 0x4e, 0x30, 0x22, 0x14, 0x06,
+	0xe8, 0xfa, 0xcc, 0xde, 0xa0, 0xb2, 0x84, 0x96,
+	0x2e, 0x3c, 0x0a, 0x18, 0x66, 0x74, 0x42, 0x50,
+	0xbe, 0xac, 0x9a, 0x88, 0xf6, 0xe4, 0xd2, 0xc0,
+	0x1c, 0x0e, 0x38, 0x2a, 0x54, 0x46, 0x70, 0x62,
+	0x8c, 0x9e, 0xa8, 0xba, 0xc4, 0xd6, 0xe0, 0xf2,
+}
+
+var crcITU_Table = [256]uint16{
+	0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
+	0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
+	0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
+	0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
+	0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
+	0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
+	0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
+	0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
+	0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
+	0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
+	0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12,
+	0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
+	0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41,
+	0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
+	0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70,
+	0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
+	0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
+	0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
+	0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
+	0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
+	0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
+	0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
+	0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
+	0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
+	0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
+	0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3,
+	0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
+	0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92,
+	0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
+	0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
+	0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
+	0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0,
+}
diff --git a/rp2-pio/piolib/sdio.pio b/rp2-pio/piolib/sdio.pio
new file mode 100644
index 0000000..524124d
--- /dev/null
+++ b/rp2-pio/piolib/sdio.pio
@@ -0,0 +1,70 @@
+; https://github.com/raspberrypi/pico-extras/blob/master/src/rp2_common/pico_sd_card/sd_card.pio
+;
+; Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
+;
+; SPDX-License-Identifier: BSD-3-Clause
+;
+
+; NOTE IT IS IMPERATIVE THAT YOU DON"T SCREW UP THE CLOCK EVEN FOR ONE HALF CYCLE, OTHERWISE THE DEVICE WILL LIKELY BE DISPLEASED AND MAY SEND GARBAGE (EVEN IF IT ISN"T DOING ANYTHING IMPORTANT WHEN YOU DO SO)
+
+.define sd_irq_num 7
+
+.program sdClk
+.side_set 1
+.wrap_target
+    irq sd_irq_num              side 1
+    irq clear sd_irq_num        side 0
+.wrap
+
+
+.program sdCmdOrDat
+.origin 0 ; must load at zero (offsets are hardcoded in instruction stream)
+public noArgStateWaitHigh:      ; this is a no arg state which means it must always appear in the second half of a word
+    ; make sure pins are hi when we set output dir (note if we are 1 bit we'll be configured for 1 pin only, so sending 0b1111 is fine)
+    set pins, 0b1111
+    set pindirs, 0b1111 
+
+public noArgStateWaitForCmdBits:
+    out exec, 16                    ; expected to be a jmp to a state
+
+public stateSendBits:
+    out x, 16
+    wait 0 irq sd_irq_num
+send_loop1:
+    out pins, 1
+    jmp x-- send_loop1
+
+public stateInlineInstruction:
+    out exec, 16                     ; may be any instruction
+.wrap_target
+    out exec, 16                     ; expected to be a jmp to a state
+
+public stateRxBits:
+    out x, 16
+    set pindirs, 0
+    wait 1 pin, 0
+    wait 0 pin, 0
+    wait 0 irq sd_irq_num
+    ; note we use wrap setup to configure receive bit/nibble transfers
+public wrapFor4bitRx:
+receive_loop1:
+    in pins, 1
+    jmp x-- receive_loop1
+.wrap
+
+; #if INCLUDE_4BIT
+public wrapTargetFor4bitRx:
+receive_loop4:
+    in pins, 4
+    jmp x-- receive_loop4
+    out exec, 16                      ; expected to be a jmp to a state
+; #endif
+
+% go {
+//go:build rp2040
+package piolib
+
+import (
+    pio "github.com/tinygo-org/pio/rp2-pio"
+)
+%}
\ No newline at end of file
diff --git a/rp2-pio/piolib/sdio_pio.go b/rp2-pio/piolib/sdio_pio.go
new file mode 100644
index 0000000..ba36610
--- /dev/null
+++ b/rp2-pio/piolib/sdio_pio.go
@@ -0,0 +1,69 @@
+// Code generated by pioasm; DO NOT EDIT.
+
+//go:build rp2040
+package piolib
+import (
+    pio "github.com/tinygo-org/pio/rp2-pio"
+)
+// sdClk
+
+const sdClkWrapTarget = 0
+const sdClkWrap = 1
+
+var sdClkInstructions = []uint16{
+		//     .wrap_target
+		0xd007, //  0: irq    nowait 7        side 1     
+		0xc047, //  1: irq    clear 7         side 0     
+		//     .wrap
+}
+const sdClkOrigin = -1
+func sdClkProgramDefaultConfig(offset uint8) pio.StateMachineConfig {
+	cfg := pio.DefaultStateMachineConfig()
+	cfg.SetWrap(offset+sdClkWrapTarget, offset+sdClkWrap)
+	cfg.SetSidesetParams(1, false, false)
+	return cfg;
+}
+
+// sdCmdOrDat
+
+const sdCmdOrDatWrapTarget = 8
+const sdCmdOrDatWrap = 15
+
+const sdCmdOrDatoffset_noArgStateWaitHigh = 0
+const sdCmdOrDatoffset_noArgStateWaitForCmdBits = 2
+const sdCmdOrDatoffset_stateSendBits = 3
+const sdCmdOrDatoffset_stateInlineInstruction = 7
+const sdCmdOrDatoffset_stateRxBits = 9
+const sdCmdOrDatoffset_wrapFor4bitRx = 14
+const sdCmdOrDatoffset_wrapTargetFor4bitRx = 16
+
+var sdCmdOrDatInstructions = []uint16{
+		0xe00f, //  0: set    pins, 15                   
+		0xe08f, //  1: set    pindirs, 15                
+		0x60f0, //  2: out    exec, 16                   
+		0x6030, //  3: out    x, 16                      
+		0x2047, //  4: wait   0 irq, 7                   
+		0x6001, //  5: out    pins, 1                    
+		0x0045, //  6: jmp    x--, 5                     
+		0x60f0, //  7: out    exec, 16                   
+		//     .wrap_target
+		0x60f0, //  8: out    exec, 16                   
+		0x6030, //  9: out    x, 16                      
+		0xe080, // 10: set    pindirs, 0                 
+		0x20a0, // 11: wait   1 pin, 0                   
+		0x2020, // 12: wait   0 pin, 0                   
+		0x2047, // 13: wait   0 irq, 7                   
+		0x4001, // 14: in     pins, 1                    
+		0x004e, // 15: jmp    x--, 14                    
+		//     .wrap
+		0x4004, // 16: in     pins, 4                    
+		0x0050, // 17: jmp    x--, 16                    
+		0x60f0, // 18: out    exec, 16                   
+}
+const sdCmdOrDatOrigin = 0
+func sdCmdOrDatProgramDefaultConfig(offset uint8) pio.StateMachineConfig {
+	cfg := pio.DefaultStateMachineConfig()
+	cfg.SetWrap(offset+sdCmdOrDatWrapTarget, offset+sdCmdOrDatWrap)
+	return cfg;
+}
+