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3.4 KiB
3.4 KiB
interface1
A serial attached Arduino interface using the National Semiconductor DP8340 and DP8341.
Hardware
You can find the Gerber files for fabricating a PCB in the fabrication directory. I have used JLCPCB to make the PCBs.
This interface requires an Arduino Mega 2560 R3.
| Item | Quantity | Description | Reference | Part Number | Source |
|---|---|---|---|---|---|
| 1 | 1 | IBM 3270 Protocol Transmitter | U1 | National Semiconductor DP8340 | Obsolete - eBay |
| 2 | 1 | IBM 3270 Protocol Receiver | U2 | National Semiconductor DP8341 | Obsolete - eBay |
| 3 | 1 | Quad RS-422 Line Driver | U3 | Texas Instruments DS3487 | Obsolete - eBay |
| 4 | 1 | Pulse Transformer - 1:1:1 | T1 | Pulse PE-5762 | Obsolete - eBay |
| 5 | 1 | Crystal - 18.867 MHz | Y1 | IQD LFXTAL057125 * | Mouser |
| 6 | 2 | Resistor - 33 ohm | R2, R4 | Mouser | |
| 7 | 1 | Resistor - 120 ohm | R6 | Mouser | |
| 8 | 2 | Resistor - 150 ohm | R1, R5 | Mouser | |
| 9 | 1 | Resistor - 500 ohm | R7 | Mouser | |
| 10 | 1 | Resistor - 510 ohm | R3 | Mouser | |
| 11 | 1 | Capacitor - 30 pF | C1 | Mouser | |
| 12 | 3 | Capacitor - 0.1 uF | C2, C3, C4 | Mouser | |
| 13 | 1 | BNC Jack | J1 | Mouser |
* - SMD
Firmware
The firmware currently provides the ability to send commands and receive responses - it is designed to implement a terminal controller, not a terminal.
You will need PlatformIO to build and upload the firmware, only Platform IO Core (the CLI) is required.
To build and upload the firmware for an Arduino Mega 2560 R3:
platformio run -t upload -e mega2560
For an original Arduino Mega:
platformio run -t upload -e mega1280