Based on the project by Kris Sekula:
GitHub: https://github.com/Kris-Sekula/EPROM-EMU-NG
I developed a version where the TTL logic was replaced by a CPLD. This made the circuit much smaller.
Instead of the Arduino Nano I directly integrated an ATMega32u4. This is flashed with the bootloader of the Arduino Micro (Using a simple ISP programmer). After that, the firmware can be flashed via USB at any time using the Arduino IDE.
PCB Version 1.3B
Current version of the board.
The assembly is done from large to small. So first the biggest parts, like CPLD, ATMega, etc. are soldered on. Then in descending order the other parts, except the EEPROM.
This should be soldered only after the bootloader for the ATMega has been flashed. Otherwise there can be problems with flashing.
When all parts, except the EEPROM, are soldered, it goes to the flashing of the Arduino bootloader.
For this purpose, there is a corresponding connector on the back. The easiest way to flash the bootloader is with Pogo PINs or a simple pin header, which are pressed onto the contacts.
A USBasp can be used for programming, for example. And with the Arduino IDE the bootloader can then be uploaded.
It is important that the Arduino Micro is selected here.
If the bootloader has been installed successfully, the EEPROM can now be soldered on.
First the EPROM Emulator NG II can be connected to the PC via USB. With the help of the Arduino IDE the ATMega is programmed first.
The current firmware can be found at https://github.com/Kris-Sekula/EPROM-EMU-NG/tree/master/Firmware.
After that the CPLD has to be programmed. This can be done most easily with a FT232H board. These adapters are available at AliExpress already around $8. And as software xc3sprog is used. This is the easiest and fastest way to flash the CPLD.
At https://github.com/1c3d1v3r/neatPLA/tree/master/programming you can find a practical instruction how to proceed.
Now the EPROM Emulator NG II is ready for use.
The software for operation and control can be downloaded from https://github.com/Kris-Sekula/EPROM-EMU-NG/tree/master/Software.
| No# | Designator | Part | Description |
|---|---|---|---|
| 1 | U1 | Alliance Memory AS6C1008-55STIN | SRAM Memory, 1048576bit, 2.7 5.5 V, 55ns 32-Pin STSOP |
| 2 | U2 | ATMEL ATMEGA32U4-AU | MCU, 8BIT, MEGAAVR, 16MHZ, TQFP-44 |
| 3 | U3 | Xilinx XC95144XL-10TQ100C | IC CPLD 144MC 10NS 100TQFP |
| 4 | U4 | MaxLinear SPX5205M5-L-3-3/TR | LDO Regulator Pos 3.3V 0.15A 5-Pin SOT-23 T/R |
| 5 | U5 | Microchip 25LC512-I/SN | IC, SM, EEPROM, SERIAL, 512K, SOIC8 |
| 6 | Q1 | ON SEMICONDUCTOR MMBT4403LT1G | Bipolar (BJT) Single Transistor, PNP, General Purpose, SOT-23-3 |
| 7 | Q2 | ON SEMICONDUCTOR MMBT4401 | Bipolar (BJT) Single Transistor, NPN, General Purpose, SOT-23-3 |
| 8 | D2 | STMICROELECTRONICS TMMBAT48FILM | Small Signal Schottky Diode, MiniMELF |
| 9 | D3 | WÜRTH ELEKTRONIK 151033RS03000 | LED, 3MM, RED, Pitch 2.54mm |
| 10 | D4 | WÜRTH ELEKTRONIK 151033GS03000 | LED, 3MM, GREEN, Pitch 2.54mm |
| 11 | D6, D8 | WÜRTH ELEKTRONIK 150060YS55040 | LED YELLOW DIFFUSED 0603 SMD |
| 12 | D7 | MCC SS14FL-TP | DIODE SCHOTTKY 40V 1A DO221AC |
| 13 | DZ1 | STMICROELECTRONICS USBLC6-2SC6 | TVS DIODE 5.25V 17V SOT23-6 |
| 14 | Y1 | Raltron Electronics R2016-16.000-9-1010-TR-NS1 | 16MHz ±10ppm 9pF 200Ω SMD,2.0x1.6mm SMD Crystal |
| 15 | F1 | Littlefuse 1206L150THWR | PTC RESET FUSE 8V 1.5A 1206 |
| 16 | F2 | Littlefuse 1210L020WR | PPTC Resettable Fuse, SMD, POLYFUSE 1210L Series, 200 mA, 400 mA, 30 VDC |
| 17 | C1, C3-C13, C19 | Murata GRM155R71A104KA01 | 0.1µF ±10% 10V Ceramic Capacitor X7R 0402 (1005 Metric) |
| 18 | C2, C14 | KEMET C0603C105K3RACTU | 1F Multilayer Ceramic Capacitor (MLCC) 25 V 10% X7R dielectric C SMD max op. temp. +125C |
| 19 | C15, C16 | KEMET C0603C220J5RACTU | Cap Ceramic 22pF 50V X7R 5% SMD 0603 125°C Punched Paper T/R |
| 20 | C17, C18 | KEMET C0805C106K8RACTU | CAP, 10µF, 10V, 10%, X7R, 0805 |
| 21 | R1, R4, R7, R13, R14 | Yageo RC0603FR-071KL | RES SMD 1K OHM 1% 1/10W 0603 |
| 22 | R2, R3 | Yageo RC0603FR-0722RL | RES SMD 22 OHM 1% 1/10W 0603 |
| 23 | R5, R6, R9 | Yageo RC0603FR-0710KL | RES SMD 10K OHM 1% 1/10W 0603 |
| 24 | R10, R11 | Yageo RC0603FR-0710RL | RES SMD 10 OHM 1% 1/10W 0603 |
| 25 | R12 | Yageo RC0603FR-074K7L | RES SMD 4.7K OHM 1% 1/10W 0603 |
| 26 | CN1 | Würth Elektronik 629105150521 | Socket micro-USB B 5P |
| 27 | CN3 | MPE Garry 369-1-014-0-NTX-KT0 | Conn Wire to Board HDR 14 POS 1.27mm Solder ST Thru-Hole |
| 28 | CN4 | TE Connectivity AMP 5499345-8 | Conn Ejector Header HDR 34 POS 2.54mm Solder RA Thru-Hole |
| 29 | SW1 | ITT C&K RS-282G05A3-SMRT | SWITCH TACTILE SPST-NO 0.05A 12V |
| 30 | SW2 | Würth Electronics 430476085716 | Black Button Tactile Switch, NO 50 mA 5mm Through Hole |
The PCB can either be ordered directly from PCBWay, or you can create it yourself from the Gerber files available here.
If you liked my project, I would be very happy about a small coffee donation.
The content of this repository, except for the Arduino code is released under the following license:
- the "Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License" (CC BY-NC-SA 4.0) full text of this license is included in the LICENSE.CC-NC-BY-SA-4.0 file and a copy can also be found at https://creativecommons.org/licenses/by-nc-sa/4.0/
