[ESP32]ESP32引脚资源分配与使用建议

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文章更新版本	时间	更新说明	修订人
V0.1	发布于2019-11-20	初始版本	libo
V0.2	发布于2020-04-24	修正表格格式	libo

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一、ESP32-D2WD芯片

1. ESP32-D2WD特殊引脚查询表&注意事项

引脚名	芯片No.	电源	是否建议使用	原因
GPIO0	23	VDD3P3_RTC	不优先	Strapping Pins* 用于切换Booting Mode 复位完成后可以正常使用
GPIO2	22	VDD3P3_RTC	不优先	Strapping Pins* 用于切换Booting Mode 复位完成后可以正常使用
GPIO5	34	VDD3P3_CPU	不优先	Strapping Pins* 与MTDO 用于切换Timing of SDIO Slave
GPIO12 /MTDI	18	VDD3P3_RTC	不优先	Strapping Pins* 用于确认flash工作电压 1:1.8v 0:3.3v(default)
GPIO15 /MTDO	21	VDD3P3_RTC	不优先	Strapping Pins* 时钟相关
GPIO16*	25	VDD_SDIO	不建议	需查阅模组原理图 GPIO16 和 GPIO17 SD_CMD, SD_CLK, SD_DATA_0 SD_DATA_1 用于外接flash
GPIO17*	27	VDD_SDIO	不建议	需查阅模组原理图 同上 （该引脚电压与flash供电电压一致）
GPIO 34 /VDET_1	10	VDD3P3_RTC	不建议	只能作为输入引脚
GPIO 35 /VDET_2	11	VDD3P3_RTC	不建议	只能作为输入引脚
GPIO 36 /SENSOR_VP	5	VDD3P3_RTC	不建议	只能作为输入引脚
GPIO 37 /SENSOR_CAPP	6	VDD3P3_RTC	不建议	只能作为输入引脚
GPIO 38 /SENSOR_CAPN	7	VDD3P3_RTC	不建议	只能作为输入引脚
GPIO 39 /SENSOR_VN	8	VDD3P3_RTC	不建议	只能作为输入引脚

1. ESP32 has five strapping pins: • MTDI • GPIO0 • GPIO2 • MTDO • GPIO5
2. 注意GPIO16、GPIO17在ESP32-WROOM-32D模组中并没有用于连接flash，且该模组flash为3.3v，所以能够在没有其他IO资源的情况下使用。In most cases, the data port connection between the ESP32 and external flash is as follows: SD_DATA0/SPIQ =IO1/DO, SD_DATA1/SPID = IO0/DI, SD_DATA2/SPIHD = IO3/HOLD#, SD_DATA3/SPIWP = IO2/WP#.

2. ESP32-D2WD芯片封装

3. ESP32-D2WD芯片引脚定义

Name	No.	Type	Function
-	-	-	Analog
VDDA	1	P	Analog power supply (2.3V – 3.6V)
LNA_IN	2	I/O	RF input and output
VDD3P3	3	P	Analog power supply (2.3V – 3.6V)
VDD3P3	4	P	Analog power supply (2.3V – 3.6V)
-	-	-	VDD3P3_RTC
SENSOR_VP	5	I	GPIO36, ADC1_CH0, RTC_GPIO0
SENSOR_CAPP	6	I	GPIO37, ADC1_CH1, RTC_GPIO1
SENSOR_CAPN	7	I	GPIO38, ADC1_CH2, RTC_GPIO2
SENSOR_VN	8	I	GPIO39, ADC1_CH3, RTC_GPIO3
CHIP_PU	9	I	High: On; enables the chip Low: Off; the chip powers off Note: Do not leave the
VDET_1	10	I	GPIO34, ADC1_CH6, RTC_GPIO4
VDET_2	11	I	GPIO35, ADC1_CH7, RTC_GPIO5
32K_XP	12	I/O	GPIO32, ADC1_CH4, RTC_GPIO9, TOUCH9, 32K_XP (32.768 kHz crystal oscillator input)
32K_XN	13	I/O	GPIO33, ADC1_CH5, RTC_GPIO8, TOUCH8, 32K_XN (32.768 kHz crystal oscillator output)
GPIO25	14	I/O	GPIO25, ADC2_CH8, RTC_GPIO6, DAC_1, EMAC_RXD0
GPIO26	15	I/O	GPIO26, ADC2_CH9, RTC_GPIO7, DAC_2, EMAC_RXD1
GPIO27	16	I/O	GPIO27, ADC2_CH7, RTC_GPIO17, TOUCH7, EMAC_RX_DV
MTMS	17	I/O	GPIO14, ADC2_CH6, RTC_GPIO16, TOUCH6, EMAC_TXD2, HSPICLK, HS2_CLK, SD_CLK, MTMS
MTDI	18	I/O	GPIO12, ADC2_CH5, RTC_GPIO15, TOUCH5, EMAC_TXD3, HSPIQ, HS2_DATA2, SD_DATA2, MTDI
VDD3P3_RTC	19	P	Input power supply for RTC IO (2.3 V – 3.6 V)
MTCK	20	I/O	GPIO13, ADC2_CH4, RTC_GPIO14, TOUCH4, EMAC_RX_ER, HSPID, HS2_DATA3, SD_DATA3, MTCK
MTDO	21	I/O	GPIO15, ADC2_CH3, RTC_GPIO13, TOUCH3, EMAC_RXD3, HSPICS0, HS2_CMD, SD_CMD, MTDO
GPIO2	22	I/O	GPIO2, ADC2_CH2, RTC_GPIO12, TOUCH2, HSPIWP, HS2_DATA0, SD_DATA0
GPIO0	23	I/O	GPIO0, ADC2_CH1, RTC_GPIO11, TOUCH1, EMAC_TX_CLK,CLK_OUT1,
GPIO4	24	I/O	GPIO4, ADC2_CH0, RTC_GPIO10, TOUCH0, EMAC_TX_ER, HSPIHD, HS2_DATA1, SD_DATA1
-	-	-	VDD_SDIO
GPIO16	25	I/O	GPIO16, HS1_DATA4, U2RXD, EMAC_CLK_OUT
VDD_SDIO	26	P	Output power supply: 1.8 V or the same voltage as VDD3P3_RTC
GPIO17	27	I/O	GPIO17, HS1_DATA5, U2TXD, EMAC_CLK_OUT_180
SD_DATA_2	28	I/O	GPIO9, HS1_DATA2, U1RXD, SD_DATA2, SPIHD
SD_DATA_3	29	I/O	GPIO10, HS1_DATA3, U1TXD, SD_DATA3, SPIWP
SD_CMD	30	I/O	GPIO11, HS1_CMD, U1RTS, SD_CMD, SPICS0
SD_CLK	31	I/O	GPIO6, HS1_CLK, U1CTS, SD_CLK, SPICLK
SD_DATA_0	32	I/O	GPIO7, HS1_DATA0, U2RTS, SD_DATA0, SPIQ
SD_DATA_1	33	I/O	GPIO8, HS1_DATA1, U2CTS, SD_DATA1, SPID
-	-	-	VDD3P3_CPU
GPIO5	34	I/O	GPIO5, HS1_DATA6, VSPICS0, EMAC_RX_CLK
GPIO18	35	I/O	GPIO18, HS1_DATA7, VSPICLK
GPIO23	36	I/O	GPIO23, HS1_STROBE, VSPID
VDD3P3_CPU	37	P	Input power supply for CPU IO (1.8 V – 3.6 V)
GPIO19	38	I/O	GPIO19, U0CTS, VSPIQ, EMAC_TXD0
GPIO22	39	I/O	GPIO22, U0RTS, VSPIWP, EMAC_TXD1
U0RXD	40	I/O	GPIO3, U0RXD, CLK_OUT2
U0TXD	41	I/O	GPIO1, U0TXD, CLK_OUT3, EMAC_RXD2
GPIO21	42	I/O	GPIO21, VSPIHD, EMAC_TX_EN
-	-	-	Analog
VDDA	43	P	Analog power supply (2.3 V – 3.6 V)
XTAL_N	44	O	External crystal output
XTAL_P	45	I	External crystal input
VDDA	46	P	Analog power supply (2.3 V – 3.6 V)
CAP2	47	I	Connects to a 3 nF capacitor and 20 kΩ resistor in parallel to CAP1
CAP1	48	I	Connects to a 10 nF series capacitor to ground
GND	49	P	Ground

二、ESP32-WROOM-32D模组

ESP32-WROOM-32D（或32U）模组内置ESP32-D0WD双核芯片，40MHz晶振，32Mbit 3.3V flash 和板载天线。

1. ESP32-WROOM-32D模组特殊引脚&注意事项

• 遵循第一节ESP32-D2WD特殊引脚查询表&注意事项

2. ESP32-WROOM-32D优先使用引脚

优先>不优先>不建议>禁用

引脚名	芯片No.	电源	是否建议使用	备注/原因
模组左侧	-	-	-	-
GPIO34*	10	VDD3P3_RTC	不建议	仅输入
GPIO35*	11	VDD3P3_RTC	不建议	仅输入
GPIO32	12	VDD3P3_RTC	优先
GPIO33	13	VDD3P3_RTC	优先
GPIO25	14	VDD3P3_RTC	优先
GPIO26	15	VDD3P3_RTC	优先
GPIO27	16	VDD3P3_RTC	优先
GPIO14	17	VDD3P3_RTC	优先	MTMS
GPIO12*	18	VDD3P3_RTC	不建议	MTDI 用于选择 flash 电压
模组下侧	-	-	-	-
GPIO13	20	VDD3P3_RTC	优先	MTCK
GPIO15*	21	VDD3P3_RTC	不建议	MTDO
GPIO2*	22	VDD3P3_RTC	不建议	用于选择 boot mode
模组右侧	-	-	-	-
GPIO23	36	VDD3P3_CPU	优先
GPIO22	39	VDD3P3_CPU	优先
GPIO21	42	VDD3P3_CPU	优先
GPIO19	38	VDD3P3_CPU	优先
GPIO18	35	VDD3P3_CPU	优先
GPIO5	34	VDD3P3_CPU	优先
GPIO17*	27	VDD_SDIO	不优先	在该模组中未用于连接flash
GPIO16*	25	VDD_SDIO	不优先	在该模组中未用于连接flash
GPIO4	24	VDD3P3_RTC	优先
GPIO0*	23	VDD3P3_RTC	不建议	用于选择 boot mode

3. ESP32-WROOM-32D模组封装

4. ESP32-WROOM-32D模组引脚定义

名称	编号	类型	功能
GND	1	P	接地
3V3	2	P	供电
EN	3	I	使能模组，高电平有效。
SENSOR_VP	4	I	GPIO36,ADC1_CH0,RTC_GPIO0
SENSOR_VN	5	I	GPIO39,ADC1_CH3,RTC_GPIO3
IO34	6	I	GPIO34,ADC1_CH6,RTC_GPIO4
IO35	7	I	GPIO35,ADC1_CH7,RTC_GPIO5
IO32	8	I/O	GPIO32,XTAL_32K_P(32.768kHz晶振输入),ADC1_CH4,TOUCH9,RTC_GPIO9
IO33	9	I/O	GPIO33,XTAL_32K_N(32.768kHz晶振输出),ADC1_CH5,TOUCH8,RTC_GPIO8
IO25	10	I/O	GPIO25,DAC_1,ADC2_CH8,RTC_GPIO6,EMAC_RXD0
IO26	11	I/O	GPIO26,DAC_2,ADC2_CH9,RTC_GPIO7,EMAC_RXD1
IO27	12	I/O	GPIO27,ADC2_CH7,TOUCH7,RTC_GPIO17,EMAC_RX_DV
IO14	13	I/O	GPIO14,ADC2_CH6,TOUCH6,RTC_GPIO16,MTMS,HSPICLK,HS2_CLK,SD_CLK,EMAC_TXD2
IO12	14	I/O	GPIO12,ADC2_CH5,TOUCH5,RTC_GPIO15,MTDI,HSPIQ,HS2_DATA2,SD_DATA2,EMAC_TXD3
GND	15	P	接地
IO13	16	I/O	GPIO13,ADC2_CH4,TOUCH4,RTC_GPIO14,MTCK,HSPID,HS2_DATA3,SD_DATA3,EMAC_RX_ER
SHD/SD2*	17	I/O	GPIO9,SD_DATA2,SPIHD,HS1_DATA2,U1RXD
SWP/SD3*	18	I/O	GPIO10,SD_DATA3,SPIWP,HS1_DATA3,U1TXD
SCS/CMD*	19	I/O	GPIO11,SD_CMD,SPICS0,HS1_CMD,U1RTS
SCK/CLK*	20	I/O	GPIO6,SD_CLK,SPICLK,HS1_CLK,U1CTS
SDO/SD0*	21	I/O	GPIO7,SD_DATA0,SPIQ,HS1_DATA0,U2RTS
SDI/SD1*	22	I/O	GPIO8,SD_DATA1,SPID,HS1_DATA1,U2CTS
IO15	23	I/O	GPIO15,ADC2_CH3,TOUCH3,MTDO,HSPICS0,RTC_GPIO13,HS2_CMD,SD_CMD,EMAC_RXD3
IO2	24	I/O	GPIO2,ADC2_CH2,TOUCH2,RTC_GPIO12,HSPIWP,HS2_DATA0,SD_DATA0
IO0	25	I/O	GPIO0,ADC2_CH1,TOUCH1,RTC_GPIO11,CLK_OUT1,EMAC_TX_CLK
IO4	26	I/O	GPIO4,ADC2_CH0,TOUCH0,RTC_GPIO10,HSPIHD,HS2_DATA1,SD_DATA1,EMAC_TX_ER
IO16	27	I/O	GPIO16,HS1_DATA4,U2RXD,EMAC_CLK_OUT
IO17	28	I/O	GPIO17,HS1_DATA5,U2TXD,EMAC_CLK_OUT_180
IO5	29	I/O	GPIO5,VSPICS0,HS1_DATA6,EMAC_RX_CLK
IO18	30	I/O	GPIO18,VSPICLK,HS1_DATA7
IO19	31	I/O	GPIO19,VSPIQ,U0CTS,EMAC_TXD0
NC	32	-	-
IO21	33	I/O	GPIO21,VSPIHD,EMAC_TX_EN
RXD0	34	I/O	GPIO3,U0RXD,CLK_OUT2
TXD0	35	I/O	GPIO1,U0TXD,CLK_OUT3,EMAC_RXD2
IO22	36	I/O	GPIO22,VSPIWP,U0RTS,EMAC_TXD1
IO23	37	I/O	GPIO23,VSPID,HS1_STROBE
GND	38	P	接地

5. ESP32-WROOM-32D模组原理图

参考文档：esp32-wroom-32d_esp32-wroom-32u_datasheet_cn.pdf

6. ESP32-WROOM-32D外围原理图参考设计