Last Update on:26/8/00
A new version of the PICLink is available now. The old version can be still viewed under e_plink_old.htm.
The new version seems to work better than the old version when used with slow calcs like the TI82 and TI85. The old version was working with the TI89 and TI92 but not with the slow TI82 and TI85. The new version has a different pin allocation and has a different program for the PIC16F84.
In the new version of TI's Graphlink Software, TI has introduced support for the old Black link which is compatible with the '$4 Serial Link'. So it might seems as if the PICLink isn't of any use anymore, but this is not true. It is still the only homemade link of Macintosh (althoug nobody has tested it with a MAC) and can be used to connect the calc to a modem.
New: Check this page to see how to patch TI's software (under Windows NT and Windows 2000) to make it work with the parallel link (='$5 link').
This device converts data between the protocol used by the calc and the async-RS232 used by the computer. The calc sends and receives bytes in a special protocol using its 2 open-drain lines. The computers tranfers bytes using the serial protocl at 9600 bps, 8-Bit no parity and no handshaking.
The advantage of this link over the other homemade links (i.e. the "$5 parallel" and "$4 serial" links ) are:
The disadvantage over the other homemade links is the relative high price. But still the PICLink is much cheaper than the real GraphLink from TI.
This links is also somewhat slower than the other links. I was amazed to find that WTran8x was faster to use ( personaly I find it much easier to use my software than TI's one).
The circuit uses a cheap way to make the signal convertion between RS-232 level and TTL level, so cables must be short. The best way is to connect the device directly to the COM port.
The software for
the PIC16F84 can be found here: Piclink.hex