PICmicro USB Multiprogrammer and 16F690

[Jan Lichtenbelt]

The E-block PICmicro USB Multiprogrammer datasheet EB006-30-7 shows that device 16F690 (20 pin) can be used. But this E-block does not have the possibility to put a 20-pins IC on this board. How to handle?

[Steve]

The v7 of the EB006 board does have a 20-pin socket for this chip. Please see the image in the datasheet:

http://www.matrixmultimedia.com/datashe ... 6-30-7.pdf

[Jan Lichtenbelt]

Ok.
The picture on page 1 shows indeed the 20 pins sockect. I was confused by the block schematic on page 4, which does show only 8,18,28 and 40 pin.

[Steve]

Yes - the block diagram needs to be updated. The original 8-pin socket is now a 20-pin socket that accepts 8-pin, 14-pin or 20-pin PICmicros.

[Jan Lichtenbelt]

Is it possible to program microchips with 20 pins in a 18 pins socket (in earlier versions of E-Block 006) knowing that two I/O ports will not function?

[medelec35]

Hello Jan.
As you know Matrix staff would be able to give correct answer, but My answer would be: No you could not program 20 pin chips in a 18 pin socket.
Here is my reason:
To program chips you will require 5 correct connections to chip. These are VDD = +5v, VSS= 0V, VPP = High Programming Voltage, ICSPDAT = In Circuit Serial Programming Data & ICSPCLK = In Circuit Serial Programming Clock.

Code: Select all

                             18 pin devices             20 pin devices                       
 VDD -                           14                              1
 VSS -                           5                               20
 VPP -                           4                               4 
ICSPDAT -                       13                              19 
ICSPCLK  -                      12                              18

So Take VDD for example. With 18 pins, VDD is physically on the right whereas with 20 pins VDD is physically on the left

[Steve]

Jan - Medelec's correct - you cannot program the 20-pin chips in 18-pin socket.

However, you can program the 20-pin chip in the 8-pin (or 14-pin) socket. Just make sure the chip's pin 1 is inserted into pin 1 of the socket. The lower part of the chip will overhang the socket, but all of the required programming pins will be connected ok.