Early mornig fun. Just changed the driver to use USB (CH340G) and added a separate 12V supply and some jumpers to select power Source. It can now be driven from 12V or 5V and you can use 12V for PWM’s while using USB 5V for ESP32 etc to have some isolation. Also added pull-up for…
We have a lot of space on the Utility Driver, so I can afford to add some TVS diodes on the ports that go directly out. These are 3.3V and can only handle 6-12mA out – basically they can just about drive a Led with some care. I also need to change UART0 pins +…
I found this schematics on esp32.com forum. I will add pull-up resistors on GPIO0 and EN as well as route them to the extension bus on the TCS. I also need to change pins so I use pin 34/35 as UART0. UARTS can be assigned to any GPIO pins, but in this case I need…
This is a draft of the Utility Driver. Basically this is a ESP32 based driver board with 7 PWM lines, 2 H-Bridges, 12 IO lines and a RS-X connection. The board can be used as a wired/wireless utility board. ESP32 Wroom 7×2 PWM connectors 2 x H-Bridge Motor ports RS-X port w 12V Power inn.…
With a small controller in each train I need a standard wireless router, a train central and Train Utility Drivers to have a complete system. I also need a HMI, but I will use the HMI Browser for this. The Utility Driver based on ESP32 (actually ESP WROOM 32) already contains Wifi/Bluetooth. But it is…
This shows the new Train Model Control System based on ESP-WROOM-32. The full size is 19.5 x 26.6 mm. The old one was 20 x 30 and I needed to cut it down from 30 to fit in my smallest cockpit. Pin 1,2 & 9 are GPIO. Pin 7 & 8 can also be used…
This is the block diagram for the ESP32 alternative. The parts in yellow is the new board mad in the same size as the ESP-WROOM-32 breakout and mounted back to back. The total cost of this should be < 10.- USD, but it is very board. The PCB is a bit of a challenge with…
ESP32 and it’s breakout board ESP-WROOM32 actually impresses me. Expressif surpriced everyone with ESP8288 a few years back, but ESP32 is a serious upgrade. Just look at this list: Supported in Arduino IDE. Straight forward to develope custom solutions. 38 pin IO Dual core 32-bit 240Mhz MCU – 600 DMIPS performance. Floating Point Unit &…
An interesting option is the ESP32 WROOM breakout board. This comes with wifi and bluetooth and a very powerfully MCU. More important is that it support wifi security, cost ca 3.5 USD and measure 18 x 25.5 mm in size. If I use this as MCU I only need to worry about the H-Bridge, PSU…
It is now ca 2 year since I started this blog writing about a Model Train Control System. The system had several newbie issues, but what stalled me was the 40Khz sender I needed for the position system. I never found components with correct size and cost that could do the job. The design itself…