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#1
STMP1 / Re: CAN controllers on STMP157...
Last post by LubOlimex - Today at 09:27:34 AM- About the jumper, it is there for compatibility reasons. If we decide to put other CAN controller. It makes no sense to change it with the CAN controller that we currently use (since it is 5V only), but we have used controllers in the past that could work at 3.3V and 5V.
- About timestamping - the hardware combo supports timestamping, it comes from the STM32MP157 chip. Can't say if I tested if the software supports it but even if it doesn't it shouldn't be hard to get it working.
- About the box - we don't have a custom box, however, the STMP board fits in the LIME metal box. There is just some free space at the side of the CAN controller (since the STMP board has no HDMI), check the pictures for each side:
The box is this one:
https://www.olimex.com/Products/OLinuXino/BOXES/BOX-LIME/
- About the software, I know for sure that in both STMP157 designs the CAN connector is tested empirically so there is CAN support in our Linux image. I can't say if in the OLinuXino board the second CAN is supported by the software (or if it can be enabled by the commands), but you can probably check the Linux configuration for the BASE EVB board (which has two CAN connectors):
https://www.olimex.com/Products/SOM/STMP1/STMP157-BASE-SOM-EVB/open-source-hardware
It is also good idea to take a look at this document about the Olimage Linux:
https://github.com/OLIMEX/olimage
- About timestamping - the hardware combo supports timestamping, it comes from the STM32MP157 chip. Can't say if I tested if the software supports it but even if it doesn't it shouldn't be hard to get it working.
- About the box - we don't have a custom box, however, the STMP board fits in the LIME metal box. There is just some free space at the side of the CAN controller (since the STMP board has no HDMI), check the pictures for each side:
The box is this one:
https://www.olimex.com/Products/OLinuXino/BOXES/BOX-LIME/
- About the software, I know for sure that in both STMP157 designs the CAN connector is tested empirically so there is CAN support in our Linux image. I can't say if in the OLinuXino board the second CAN is supported by the software (or if it can be enabled by the commands), but you can probably check the Linux configuration for the BASE EVB board (which has two CAN connectors):
https://www.olimex.com/Products/SOM/STMP1/STMP157-BASE-SOM-EVB/open-source-hardware
It is also good idea to take a look at this document about the Olimage Linux:
https://github.com/OLIMEX/olimage
#2
STMP1 / CAN controllers on STMP157-OLi...
Last post by dry - Today at 06:07:50 AMHello Olimex, Interested in this board,
https://www.olimex.com/Products/OLinuXino/STMP1/STMP157-OLinuXino-LIME2/open-source-hardwarea
- The chip if I'm not mistaken has 2 x CAN FD on it, are the second CAN controller pins available to connect external transceiver through board's GPIO's blocks, and Linux driver(s) can use second controller? I need to connect own external transceiver(s). If it requires alt function or muxing, what would I loose if I want second CAN, considering the stack thats running on it?
- Could you confirm that both those CAN controllers and driver supports the hardware timestmaping of messages? (i.e., its not the host's own timestamp)
- Could you explain the purpose of this 5v/3v3 switch on CAN transceiver on board, doenst' that module only support 5v CAN?
Is there a box/housing available for the board, similar to how you have for A20 Micro?
https://www.olimex.com/Products/OLinuXino/STMP1/STMP157-OLinuXino-LIME2/open-source-hardwarea
- The chip if I'm not mistaken has 2 x CAN FD on it, are the second CAN controller pins available to connect external transceiver through board's GPIO's blocks, and Linux driver(s) can use second controller? I need to connect own external transceiver(s). If it requires alt function or muxing, what would I loose if I want second CAN, considering the stack thats running on it?
- Could you confirm that both those CAN controllers and driver supports the hardware timestmaping of messages? (i.e., its not the host's own timestamp)
- Could you explain the purpose of this 5v/3v3 switch on CAN transceiver on board, doenst' that module only support 5v CAN?
Is there a box/housing available for the board, similar to how you have for A20 Micro?
#3
New Products release / BOX-ESP32-P4-PC
Last post by olimex - May 27, 2026, 01:56:12 PMWe are pleased to announce that our popular ESP32-P4-PC board now has its own dedicated 3D printed enclosure! The new BOX-ESP32-P4-PC is specially designed for the board and provides openings for all interfaces
https://olimex.wordpress.com/2026/05/27/esp32-p4-pc-now-have-plastic-box/
#esp32 #iot #oshw #esp32 #esp32p4 #espressif
https://olimex.wordpress.com/2026/05/27/esp32-p4-pc-now-have-plastic-box/
#esp32 #iot #oshw #esp32 #esp32p4 #espressif
#4
New Products release / TuxCon2026 is over
Last post by olimex - May 26, 2026, 09:31:09 AMTuxCon 2026 is over, and once again it was an amazing weekend full of talks, friends, hardware, open source, and the traditional soldering workshop at Olimex.
Huge thanks to the volunteer organizers and to everyone who joined us — from the youngest 4.5-year-old participant to the experienced makers and hackers who keep the community growing every year.
See you all at TuxCon 2027!
https://olimex.wordpress.com/2026/05/26/tuxcon-2026-has-come-to-an-end/
#tuxcon #foss #oshw #linux #soldering #workshop
Huge thanks to the volunteer organizers and to everyone who joined us — from the youngest 4.5-year-old participant to the experienced makers and hackers who keep the community growing every year.
See you all at TuxCon 2027!
https://olimex.wordpress.com/2026/05/26/tuxcon-2026-has-come-to-an-end/
#tuxcon #foss #oshw #linux #soldering #workshop
#5
New Products release / Six new models of OV5647 5-Meg...
Last post by olimex - May 25, 2026, 10:36:20 AMSix new models of OV5647 5-Megapixel cameras with adjustable lenses for ESP32-P4-DevKit and ESP32-P4-PC are in stock. NV suffix version is with IR cut-off filter removed for night vision apps. https://olimex.wordpress.com/2026/05/25/six-new-models-of-ov5647-5-megapixel-cameras-with-adjustable-lenses-for-esp32-p4-devkit-and-esp32-p4-pc-are-in-stock/ #esp32p4 #ov5647 #computervision #iot #mipi #csi #raspberrypi
#6
ESP32 / Re: Olimex ESP32 POE
Last post by LubOlimex - May 25, 2026, 08:10:33 AMEach ESP32-POE is tested empirically after manufacturing. The test includes programming at least two times.
Double check cabling, port selection, programming settings and configuration. Try with another software tool.
Try reinstalling the CH340 driver.
My advice is to also first try with the tools supported by the chip manufacturer Espressif - like esptool, ESP-IDF, ESP32 package for Arduino IDE.
Double check cabling, port selection, programming settings and configuration. Try with another software tool.
Try reinstalling the CH340 driver.
My advice is to also first try with the tools supported by the chip manufacturer Espressif - like esptool, ESP-IDF, ESP32 package for Arduino IDE.
#7
ESP32 / Re: ESP32-PoE-ISO UART1 issue
Last post by bartgrefte - May 24, 2026, 10:54:51 AMThen why does the MOD-RS485-ISO have a half-duplex mode which according to the manual is the default mode? It wasn't actually default by the way (neither was passthrough mode which required a factory reset), there was only one jumper on the board and it wasn't used for half-duplex mode.
Since it seems the MOD-RS485-ISO does not actually support half-duplex mode, why is this even in the manual and why are there jumpers for this?
Finally found the AMS1117's so that I could test the 3.3V FTDI-cable (with 5V VCC) directly on the MOD-RS485-ISO, without having the ESP32-PoE-ISO involved.
When connecting it to my laptop and testing with ModBus Poll (which I confirmed working with a RS485 USB stick) I got "insufficient bytes received" and when I checked the communication traffic the data looked the same as when I connected Rx and Tx together: what is received is the same as what was send. Is this to be expected?
Currently waiting for "dumb" RS485-UART adapters that are 3.3V compatible.
Since it seems the MOD-RS485-ISO does not actually support half-duplex mode, why is this even in the manual and why are there jumpers for this?
Finally found the AMS1117's so that I could test the 3.3V FTDI-cable (with 5V VCC) directly on the MOD-RS485-ISO, without having the ESP32-PoE-ISO involved.
When connecting it to my laptop and testing with ModBus Poll (which I confirmed working with a RS485 USB stick) I got "insufficient bytes received" and when I checked the communication traffic the data looked the same as when I connected Rx and Tx together: what is received is the same as what was send. Is this to be expected?
Currently waiting for "dumb" RS485-UART adapters that are 3.3V compatible.
#8
ESP32 / Olimex ESP32 POE
Last post by bend - May 23, 2026, 06:24:52 PMhi,
I bought 2 olimex Esp32 POE
i try to flash wled on it
it failed on both devices with running message : preparing
Any Tips to flash these devices?
regards
I bought 2 olimex Esp32 POE
i try to flash wled on it
it failed on both devices with running message : preparing
Any Tips to flash these devices?
regards
#9
ESP32 / Re: ESP32-PoE-ISO UART1 issue
Last post by LubOlimex - May 22, 2026, 08:49:47 AMNowhere did we mention that we used or tested ModBus. Never have I or any colleague explored empirically that compatibility until now.
The one thing I can try to do is to give the firmware source to AI and ask it to the change default mode of operation from full-duplex to half-duplex and make it compatible by default with Modbus and ESPEasy. I would test it a bit. If this succeeds I can send you the hex and you can change the firmware via PIC16-compatible programmer (attached over the ICSP connector) and test again.
The one thing I can try to do is to give the firmware source to AI and ask it to the change default mode of operation from full-duplex to half-duplex and make it compatible by default with Modbus and ESPEasy. I would test it a bit. If this succeeds I can send you the hex and you can change the firmware via PIC16-compatible programmer (attached over the ICSP connector) and test again.
#10
ESP32 / Re: ESP32-PoE-ISO UART1 issue
Last post by bartgrefte - May 21, 2026, 06:42:47 PM"Well, read again slowly your last reply. Voila. That is how Schottky diodes work - it blocks current from travelling in reverse direction and also why the Schottky is fine on GPI36 (it has only one direction)."
Yes, but that does not explain why I am not getting a beep with the continuity measurement between UEXT-GPI(O)36 and the one on the side of the board. Correct me if I'm wrong, but shouldn't that, just like directly over the diode, also give a result/beep in just one direction? I'm getting nothing, in either direction. Only when measuring directly over the diode I get a result.
"and there is also pull-up resistor on the wire...."
Which is not active when the circuit is unpowered, so I am still wondering why directly over the diode there's a result, but not between the two GPI(O)36 pins. If the circuit where active and with that the pullup, then yes, but during the continuity test the circuit and with that the pullup was not active.
Plus when I Googled I came across that other topic (where my startpost was split from) so I thought something might've been wrong with UART1.
"- Connect RX to TX via jumper wire like this:"
That was on my to do list, but due to a move, everything is somewhere else and partly still in boxes. Have been having problems finding stuff, like the jumper wires. Just found one, hooked it up, connected ModBus Pull (which also failed to make contact to the meters) to the serial server in ESP Easy and after checking the communication window in ModBus Pull I see Rx data that matches the Tx data and when disconnecting the jumper wire, no Rx data. So it seems the UART does work.
"it is in the compatibility between MOD-RS485-ISO's firmware and the software libraries (ESPEasy, Modbus) you'd want to use."
Including ModBus Pull on Windows which I tested through the serial server plugin on ESPEasy. Once I've found the AMS1117's (got a 3.3V FTDI-cable with a design flaw) I'm planning on testing that directly on the MOD-RS485-ISO module, see if I can rule the combination ESPEasy and MOD-RS485-ISO out.
"There is no point of using MOD-RS485-ISO if you are going to use Modbus, that is what I am saying"
Well, something like that could've been mentioned in the FAQ on the product page
, if I had known this, I would've bought something else. Though those dumb boards (MAX485 ?) aren't isolated as far as I know. Thought getting an isolated board was a good idea.
"Re-write parts of ESPEasy/Modbus so that it is compatible with MOD-RS485-ISO"
Do you have any insight on where ESPEasy's SDM*** library might be failing with this? I assumed ModBus was as simple as: Master (ESPEasy plugin) sends command with request for data from a certain register, MOD-RS485-ISO passes it along over RS485, ModBus-meter responds and sends the requested data back, MOD-RS485-ISO passes it along over UART to the ESP32.
Yes, but that does not explain why I am not getting a beep with the continuity measurement between UEXT-GPI(O)36 and the one on the side of the board. Correct me if I'm wrong, but shouldn't that, just like directly over the diode, also give a result/beep in just one direction? I'm getting nothing, in either direction. Only when measuring directly over the diode I get a result.
"and there is also pull-up resistor on the wire...."
Which is not active when the circuit is unpowered, so I am still wondering why directly over the diode there's a result, but not between the two GPI(O)36 pins. If the circuit where active and with that the pullup, then yes, but during the continuity test the circuit and with that the pullup was not active.
Plus when I Googled I came across that other topic (where my startpost was split from) so I thought something might've been wrong with UART1.
"- Connect RX to TX via jumper wire like this:"
That was on my to do list, but due to a move, everything is somewhere else and partly still in boxes. Have been having problems finding stuff, like the jumper wires. Just found one, hooked it up, connected ModBus Pull (which also failed to make contact to the meters) to the serial server in ESP Easy and after checking the communication window in ModBus Pull I see Rx data that matches the Tx data and when disconnecting the jumper wire, no Rx data. So it seems the UART does work.
"it is in the compatibility between MOD-RS485-ISO's firmware and the software libraries (ESPEasy, Modbus) you'd want to use."
Including ModBus Pull on Windows which I tested through the serial server plugin on ESPEasy. Once I've found the AMS1117's (got a 3.3V FTDI-cable with a design flaw) I'm planning on testing that directly on the MOD-RS485-ISO module, see if I can rule the combination ESPEasy and MOD-RS485-ISO out.
"There is no point of using MOD-RS485-ISO if you are going to use Modbus, that is what I am saying"
Well, something like that could've been mentioned in the FAQ on the product page
, if I had known this, I would've bought something else. Though those dumb boards (MAX485 ?) aren't isolated as far as I know. Thought getting an isolated board was a good idea."Re-write parts of ESPEasy/Modbus so that it is compatible with MOD-RS485-ISO"
Do you have any insight on where ESPEasy's SDM*** library might be failing with this? I assumed ModBus was as simple as: Master (ESPEasy plugin) sends command with request for data from a certain register, MOD-RS485-ISO passes it along over RS485, ModBus-meter responds and sends the requested data back, MOD-RS485-ISO passes it along over UART to the ESP32.