- on Computer/Software/Internet
- Published in issue 7/2012 on page 46
Gee Whiz, a GPIB-to USB Converter
$50 interface circuit brings 80s/90s edebris to life
GPIB (General Purpose Interface Bus) refers to an IEEE 488 standard parallel interface originally defined in 1984 for attaching sensors and programmable instruments to a computer. Using a 24-pin connector, up to 15 devices can be daisy chained together and addressed individually. Hewlett Packard’s version of the GPIB is unsurprisingly called HPIB.
CAM/CAD data for the PCB referred to in this article is available as a Gerber file. Elektor GREEN and GOLD members can exclusively download these files for free as part of their membership. Gerber files allow a PCB to be produced on an appropriate device available locally, or through an online PCB manufacturing service.
Elektor recommends its business partner Eurocircuits as the company of choice for its own prototypes and volume production in selected cases.
GPIB-USB Converter Features
* Low-cost external adapter
* Full GPIB / IEEE488 functionality by USB
* PIC18F2550 @ 20MHz with on-chip USB interface
* Emulation and enumeration of PC COM port
* Software developed in C and MCHPFSUSB Framework
Update. November 1, 2012.
The url for the Microchip USB Framework download has moved to:
R1,R2 = 100Ohm, DIL16 array
R4 = 270Ohm, DIL16 array
R3,R5 = 10kOhm, SIL9 array
R6 = 10kOhm
C1 = 100µF 16V, radial
C2,C3,C4 = 100nF
C5,C6 = 22pF, ceramic, lead pitch 2.5mm
C7 = 470nF
D1–D8 = LED, 3mm, red
IC1 =PIC18F2550-I/SP, programmed, Elektor # 100592-41
X1 = 20MHz quartz crystal
K1 = 4-pin pinheader, pitch 0.1’’ (2.54mm)
K2 = 6-pin pinheader, pitch 0.1’’ (2.54mm)
K3 = USB socket, Type B, PCB mount
K4 = 24-way IEEE488/Centronics connector, male, PCB mount. Alternatively, IDC version wired to board (Farnell # 1099278).
PCB # 100592