KC868-A16v3 ESP32-S3 IO pins define

[admin]

ANALOG_A1  4
ANALOG_A2  6
ANALOG_A3  7
ANALOG_A4  5

IIC Bus:

SDA:GPIO9
SCL:GPIO10

Relay_IIC_address 0x24
Relay_IIC_address 0x25

Input_IIC_address 0x21
Input_IIC_address 0x22

24C02 EPROM i2c address: 0x50
DS3231 RTC i2c address: 0x68
SSD1306 display: i2c address:0x3c

-----------------

1-wire (pull-up resistance on PCB):
1-wire1:GPIO47
1-wire2:GPIO48
1-wire3:GPIO38

free GPIOs (without pull-up resistance on PCB):
free gpio-1:GPIO39
free gpio-2:GPIO40
free gpio-3:GPIO41
-----------------

Ethernet (W5500) I/O define:

clk_pin: GPIO42
mosi_pin: GPIO43
miso_pin: GPIO44
cs_pin: GPIO15

interrupt_pin: GPIO2
reset_pin: GPIO1

--------------------
RS485:
RXD:GPIO17
TXD:GPIO16

--------------------
SD Card:
SPI-MOSI:GPIO12
SPI-SCK:GPIO13
SPI-MISO:GPIO14
SPI-CS:GPIO11
SD-CD:GPIO21

--------------------
RF433MHz wireless receiver: GPIO8
RF433MHz wireless sender: GPIO18

free gpio on PCB (beside ESP32-S3 module)
GPIO39
GPIO40
GPIO41

[kotyara12]

Hi!

How can I get the schematic for this board version? It will make it easier to develop firmware for it.

And another question: why don't you want to output interrupts from the input expanders to the ESP32? They are very necessary!

[admin]

send me your email.
ESP32 use PCF8574 enough work well without interrupt pin.

[kotyara12]

Hi!

How can I get the schematic for this board version? It will make it easier to develop firmware for it.

And another question: why don't you want to output interrupts from the input expanders to the ESP32? They are very necessary!

Hi!

I have to disagree with you. The lack of interrupts does not allow writing a handler for a pulse counter. For example, for a water flow counter or wind speed counter.

In addition, the lack of interrupts forces the programmer to poll the chip too often than necessary. You wouldn't refuse a doorbell in your house instead of walking around and checking if there is anyone at the door every 5 minutes.

On the old version (KC868-A16), I had to do some magic with the board to fix this problem on one of the two input expanders. I used the pin occupied by the RS433 receiver for this, which I do not need.

On the new version of the board, this is a little easier to do, since there are several free GPIOs. But you still have to pull the wire.

[kotyara12]

And I also don't like the protection scheme of the A and B RS485 lines: https://kotyara12.ru/wp-content/uploads/...2rs485.png
Thermal fuses are placed BETWEEN the connector and the TVS diodes, and not between the TVS diodes and the chip, as you have done. In your version, this is pointless.

[tobi.gubo]

Can you tell me the GPIO id of the RS485 RTS pin for switching between sending and receiving data?

[admin]

this RS485 circuit of KC868-A16v3.
   

[tobi.gubo]

The pins RE and DE of the MAX13487 are used to controll the data flow between sending and receiving. They are linked to vcc with RE inverted so it is always set to sending data. Since you are providing example code with also receiving data does this mean this chip automatically switches between sending and receiving?
It looks like it here: https://www.analog.com/en/products/max13487e.html

[admin]

here is RS485 arduino demo source code for KC868-A16v3: https://www.kincony.com/forum/showthread.php?tid=7385