HRPT/PDUS/CHRPT decoder print

Print lay-out decoder.

Pushing FPGA's into their sockets sometimes needs some force. Removing them without damaging them or the sockets can be difficult without proper tools. Make sure that you push the FPGA's in the right way into their sockets. But first read Put into use.

Needed jumpers and connections.


Jumpers (CON2) Only jumper 1-2 (HSEL) needed

Decoder selection decoder.

For a 512K EPROm the following connections have to be made:


If a 256k EPROM is used (which means, just HRPT and PDUS) then SX must be always closed.

SM (select decoder/generator) is not needed (selection is done by means of parallel port).

Jumpers/connections for special cases.

Channel selection with switches.

Channel selection is done by the software. This is important because the info about which channels are recorded is needed to reproduce the pictures. This info is, therefore, saved in the file together with the picture.

If you want to select channels by means of swithes this is possible by adding 6 switches to CON1, and by removing jumper HSEL (CON2, 1-2), and by removing the diodes D3-D8.

Switch between decoder and generator.

If you want to switch between decoder and generator by means of a swith instead of by means of the PC then add SM, and remove diode D9.

PCB info.

The print is designed by W. Pfeifer. The GIF-pictures are here to get an idea of the print layout. Resolution is, however, far too low to use it as a mask. Use the PDF or the postscript file instead.
GIF PDF Postscript



PCB component side.


PCB copper side.
NOTE: Scale is 1:1.414. Reduce 71% (A3 ==> A4). Picture is in reverse!