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#71
PIC / Re: PIC-USB-4550 program does ...
Last post by emil_bbb - February 11, 2026, 07:43:33 PMI have studied the souce code from PIC_USB_4550_BLINKING_LED and I cannot figure out where are those values are set.
//PROGRAMM FOR BLINKING LED
//
// PROCESSOR : PIC18F4550
// CLOCK : 20MHz, EXTERNAL
#include <p18cxxx.h>
#define BUT PORTBbits.RB4
#define LED_ON PORTDbits.RD3 = 1
#define LED_OFF PORTDbits.RD3 = 0
#define TOGGLE_LED PORTD ^= 0x08
#define INPUT 1
#define OUTPUT 0
#define LED_DIR TRISDbits.TRISD3
#define BUT_DIR TRISBbits.TRISB4
/** V E C T O R R E M A P P I N G *******************************************/
extern void _startup (void); // See c018i.c in your C18 compiler dir
#pragma code _RESET_INTERRUPT_VECTOR = 0x000800
void _reset (void)
{
_asm goto _startup _endasm
}
#pragma code
#pragma code _HIGH_INTERRUPT_VECTOR = 0x000808
void _high_ISR (void)
{
;
}
#pragma code _LOW_INTERRUPT_VECTOR = 0x000818
void _low_ISR (void)
{
;
}
#pragma code
//Just simple delay
void Delay(unsigned long cntr) {
while (--cntr != 0);
}
// Main function
void main(void) {
INTCON = 0x0; // Disable inerupt
CMCON = 0x07; // Comparators Off
ADCON1 = 0x06; // Port as Digital IO
// RDPU = 0; // Disable pull ups
PORTEbits.RDPU = 0; // Disable pull ups
CCP1CON = 0; // P1B, P1C, P1D assigned as port pins
LED_DIR = OUTPUT; // Led pin as output
BUT_DIR = INPUT; // Button pin as insput
// loop forever - echo
while(1) {
// Toggle led
TOGGLE_LED;
// Simple delay
Delay(50000);
}
}
//PROGRAMM FOR BLINKING LED
//
// PROCESSOR : PIC18F4550
// CLOCK : 20MHz, EXTERNAL
#include <p18cxxx.h>
#define BUT PORTBbits.RB4
#define LED_ON PORTDbits.RD3 = 1
#define LED_OFF PORTDbits.RD3 = 0
#define TOGGLE_LED PORTD ^= 0x08
#define INPUT 1
#define OUTPUT 0
#define LED_DIR TRISDbits.TRISD3
#define BUT_DIR TRISBbits.TRISB4
/** V E C T O R R E M A P P I N G *******************************************/
extern void _startup (void); // See c018i.c in your C18 compiler dir
#pragma code _RESET_INTERRUPT_VECTOR = 0x000800
void _reset (void)
{
_asm goto _startup _endasm
}
#pragma code
#pragma code _HIGH_INTERRUPT_VECTOR = 0x000808
void _high_ISR (void)
{
;
}
#pragma code _LOW_INTERRUPT_VECTOR = 0x000818
void _low_ISR (void)
{
;
}
#pragma code
//Just simple delay
void Delay(unsigned long cntr) {
while (--cntr != 0);
}
// Main function
void main(void) {
INTCON = 0x0; // Disable inerupt
CMCON = 0x07; // Comparators Off
ADCON1 = 0x06; // Port as Digital IO
// RDPU = 0; // Disable pull ups
PORTEbits.RDPU = 0; // Disable pull ups
CCP1CON = 0; // P1B, P1C, P1D assigned as port pins
LED_DIR = OUTPUT; // Led pin as output
BUT_DIR = INPUT; // Button pin as insput
// loop forever - echo
while(1) {
// Toggle led
TOGGLE_LED;
// Simple delay
Delay(50000);
}
}
#72
ESP32 / Re: New ESP32-POE-ISO - was I ...
Last post by chrismacp - February 11, 2026, 06:25:35 PMThanks for the tips.
I am not 100% sure which is U7. I added a photo to indicate which one I think it is (yellow arrow) or could it be the white arrow?
https://drive.google.com/file/d/15eo-CIxJKTpJbuQ3NALS_mo5YdbeBfEL/view?usp=sharing
I found the part at Mouser here
which looks more like the the component the yellow arrow is pointing at.
Once I confirm, I'll go and learn how to solder surface mount components!
I am not 100% sure which is U7. I added a photo to indicate which one I think it is (yellow arrow) or could it be the white arrow?
https://drive.google.com/file/d/15eo-CIxJKTpJbuQ3NALS_mo5YdbeBfEL/view?usp=sharing
I found the part at Mouser here
which looks more like the the component the yellow arrow is pointing at.
Once I confirm, I'll go and learn how to solder surface mount components!
#73
FPGA / Re: I've just updated my E80 C...
Last post by Stokpan - February 11, 2026, 10:26:26 AMI think the main reason for the difficulty is that the OSS-CAD suite builds for Windows do not include the GHDL plugin for Yosys. But that wasn't really necessary, all I had to do was to elaborate the project folder and a single board-specific VHDL file with GHDL and output the whole thing into a single Verilog file. After that the process is typical...
...well not so typical because I also had to find the correct driver by trial and error and also discover that the openfpgaloader in the OSS-CAD suite doesn't work whereas the one in the old Gatemate suite does.
If anyone wants a helping hand understanding my synth.bat file, let me know -- I'll be watching this topic.
...well not so typical because I also had to find the correct driver by trial and error and also discover that the openfpgaloader in the OSS-CAD suite doesn't work whereas the one in the old Gatemate suite does.
If anyone wants a helping hand understanding my synth.bat file, let me know -- I'll be watching this topic.
#74
New Products release / Making self hosted web user in...
Last post by olimex - February 10, 2026, 01:38:42 PMMaking self hosted web user interface for BME280 temperature, humidity and pressure sensor for ESP32-POE, ESP32-C6-DevKit-Lipo and ESP32-C3-Devkit-Lipo with ESPUI https://olimex.wordpress.com/2026/02/10/making-self-hosted-web-user-interface-for-bme280-temperature-humidity-and-pressure-sensor-for-esp32-poe-esp32-c6-devkit-lipo-and-esp32-c3-devkit-lipo-with-espui/ #esp32 #espui #iot #server
#75
FPGA / Re: I've just updated my E80 C...
Last post by LubOlimex - February 09, 2026, 11:53:54 AMThis is great thank you for posting it! I myself had some trouble getting the environment setup properly under Windows.
#76
ESP32 / Re: ESP32-POE-IND Rev.M
Last post by LubOlimex - February 09, 2026, 08:30:45 AMIt should be doable.
There is a lot of info online about ESPHome and HC-SR04, for ESP32-POE-IND use the ESP32-POE config:
ethernet:
type: LAN8720
mdc_pin: GPIO23
mdio_pin: GPIO18
clk:
pin: GPIO17
mode: CLK_OUT
phy_addr: 0
power_pin: GPIO12
Check here: https://esphome.io/components/ethernet/
Better check in the ESPHome forums for software help. They know their software better.
There is a lot of info online about ESPHome and HC-SR04, for ESP32-POE-IND use the ESP32-POE config:
ethernet:
type: LAN8720
mdc_pin: GPIO23
mdio_pin: GPIO18
clk:
pin: GPIO17
mode: CLK_OUT
phy_addr: 0
power_pin: GPIO12
Check here: https://esphome.io/components/ethernet/
Better check in the ESPHome forums for software help. They know their software better.
#77
PIC / Re: PIC-USB-4550 program does ...
Last post by LubOlimex - February 09, 2026, 08:27:53 AMThis is a warning that if you download that software to the chip via the bootloader it will disable the bootloader and future upload via the bootloader will not be possible (e.g. you would need to use ISP programmer for subsequent programming).
You have two options:
- Edit the configuration bits in your code so that it doesn't cause problems for the bootloader (change the bits as described in the warning - enable Table Write Protect Boot; enable USB Voltage Regulator; set Oscillator value to HS+PLL, USB-HS).
- Ignore the warnings and break the bootloader; this will require using a programmer in future programming of that chip (this might be useful for security reasons)
You have two options:
- Edit the configuration bits in your code so that it doesn't cause problems for the bootloader (change the bits as described in the warning - enable Table Write Protect Boot; enable USB Voltage Regulator; set Oscillator value to HS+PLL, USB-HS).
- Ignore the warnings and break the bootloader; this will require using a programmer in future programming of that chip (this might be useful for security reasons)
#78
ESP32 / ESP32-POE-IND Rev.M
Last post by PK - February 08, 2026, 02:25:55 PMHi,
I am not experienced on ESP32. However, I intend to use Olimex ESP32-POE-IND Rev.M for measuring distance, with e.g. HC-SR04.
Is there anyone, that could walk me through the process of making this happen? I have for instance ESPHome, running on docker. It would be great to have this device adopted into home assistant
I am not experienced on ESP32. However, I intend to use Olimex ESP32-POE-IND Rev.M for measuring distance, with e.g. HC-SR04.
Is there anyone, that could walk me through the process of making this happen? I have for instance ESPHome, running on docker. It would be great to have this device adopted into home assistant
#79
PIC / PIC-USB-4550 program does not ...
Last post by emil_bbb - February 07, 2026, 11:25:50 PMThe board works with the Blinking LED program. However when I program the F4550 with my own software, the software does not work. If I program the F4550 with my K150 the software works. Here is the message that I get when I try to execute the software after programming the F4550 with the PIC-USB-4550 board. https://ibb.co/VW4dDNrZ
What can I do in order to make my software work when I programm the F4550 with the PIC-USB-4550 board ?
What can I do in order to make my software work when I programm the F4550 with the PIC-USB-4550 board ?
#80
FPGA / I've just updated my E80 CPU p...
Last post by Stokpan - February 07, 2026, 01:06:39 AMHi everyone,
A few months ago, I completed my undergraduate thesis demonstrating that a CPU in VHDL for educational purposes is feasible using only the elementary digital design theory taught at my university. Along with the CPU, I wrote an assembler and created an environment that allows for assembly programming and simulation via GHDL with a single hotkey.
The CPU was tested on three EDAs and two FPGA boards. One of the GHDL developers recommended I try the Olimex GateMateA1-EVB, and I am glad I did.
I have spent the last month working to bring the E80 to this platform. Although the CPU is simple, the design is based 100% on structural VHDL and flip-flops; it is "novel" enough that EDAs often cannot infer their own optimized components, making it a great stress test for the open-source tools.
The hardest part was getting a stable flow running on Windows. I encountered several inconsistencies:
I also found that many existing toolchain scripts for Windows are overly complicated, often requiring subsequent runs of the same batch file with different options just to finish a build.
I worked hard to make this process as smooth as possible for the end user, providing a "one-click" batch flow that handles the version mixing and multi-file synthesis automatically. You can find the detailed setup and the Windows-specific instructions here:
https://github.com/Stokpan/E80?tab=readme-ov-file#example-3---testing-on-the-olimex-gatematea1-evb-on-windows
(Yes, I didn't use resistors for the LEDs. Two reasons: this build will soon be replaced by serial output, and I have partial color blindness which makes it really difficult to see the LEDs without full brightness)
Hopefully, this work helps other authors and students support this great and cost-effective board!
A few months ago, I completed my undergraduate thesis demonstrating that a CPU in VHDL for educational purposes is feasible using only the elementary digital design theory taught at my university. Along with the CPU, I wrote an assembler and created an environment that allows for assembly programming and simulation via GHDL with a single hotkey.
The CPU was tested on three EDAs and two FPGA boards. One of the GHDL developers recommended I try the Olimex GateMateA1-EVB, and I am glad I did.
I have spent the last month working to bring the E80 to this platform. Although the CPU is simple, the design is based 100% on structural VHDL and flip-flops; it is "novel" enough that EDAs often cannot infer their own optimized components, making it a great stress test for the open-source tools.
The hardest part was getting a stable flow running on Windows. I encountered several inconsistencies:
- The Programmer: The openFPGALoader included in the latest oss-cad-suite failed to upload—the config LED would flash for a fraction of a second, but the bitstream wouldn't stick. I found that the version in the older cc-toolchain-win package works perfectly.
- The P&R: Conversely, the older p_r utility struggled with my design, whereas the new nextpnr-himbaechel in the oss-cad-suite works flawlessly.
- The Driver: The recommended driver installation guidelines didn't work in my tests, and I had to find the correct driver from the Zadig utility by trial-and-error.
- VHDL Elaboration: Most recommended Yosys-GHDL combinations seem optimized for single-file designs. Since my project uses multiple files and custom libraries, I had to implement a specific sequence using GHDL for elaboration and Yosys for synthesis.
I also found that many existing toolchain scripts for Windows are overly complicated, often requiring subsequent runs of the same batch file with different options just to finish a build.
I worked hard to make this process as smooth as possible for the end user, providing a "one-click" batch flow that handles the version mixing and multi-file synthesis automatically. You can find the detailed setup and the Windows-specific instructions here:
https://github.com/Stokpan/E80?tab=readme-ov-file#example-3---testing-on-the-olimex-gatematea1-evb-on-windows
(Yes, I didn't use resistors for the LEDs. Two reasons: this build will soon be replaced by serial output, and I have partial color blindness which makes it really difficult to see the LEDs without full brightness)
Hopefully, this work helps other authors and students support this great and cost-effective board!