KEY64D PH
From PHCC
Contents
KEY64D_PH Keymatrix Daughterboard
Features:
- 64 inputs
- no ghosting as each input is diode protected
- connectors: pinheaders for IDC ribbon flat cables
- board size: 80x100mm (1/2 euro size)
Schematic and Layout
Bill of Materials
The BOM is here: PHCC_KEY64D_PH.BOM.txt
This list includes prices and links to to online catalogue pages of my primary source of electronics components, Reichelt Elektronik
North American users Bill of Materials media: KEY64D PH Rev0B BOM.pdf
Wiring Switches
Here is an image that illustrates how to connect switches to the key matrix board.
In order to correctly wire switches to the KEY64D_PH, you need to carefully follow the matrix layout.
The 64 switch inputs are broken out on the four connectors marked CON3 thru CON6. Each connector has two blocks of 8 inputs. Each one of those blocks matches one pair of pins on the "Common" connector, CON2.
The pins on CON2 thru CON6 are laid out like this:
15 13 11 9 7 5 3 1
16 14 12 10 8 6 4 2
For the Common block, it gives you two attach points for each common line. For example, pins 1 & 2 are bound together to form "Common #1". This is the same for 2-3, 4-5, etc.
Two quick & dirty examples: To wire in Switch #1, you'll connect one leg of the switch to pin #1 on CON3 and the other leg to either pin 1 or 2 on CON2. To wire in Switch #9, you'll connect one leg of the switch to pin #9 on CON3 and the other leg to either pin 3 or 4 on CON2.
Potential Problems
Note that if you see really odd behavior with your KEY64D_PH with ghosting, or odd input behavior like what has been described in this forum thread: http://forums.varxec.net/index.php?t=msg&th=158&start=0&rid=36 you should carefully check the orientation of the resistor networks on the PHCC motherboard (RN1 & RN2). The "polarity" of the part is important.