This is the Revision F verion of the Switch8 Module. The status of this project is finished.
This document is also available as a PDF document.
The Switch8 Module allows you to read up to 8 digital inputs. An interrupt can be generated on the states of selected inptus.
The basic operation is to send a query to the Switch8 Module to read the 4 bits of data. The programmer can download a complement mask to cause any of the bits to be complemented prior to reading.
The Switch8 Module supports Module Interrupt Protocol. The interrupt pending bit is set whenever the the formula:
L&(~I) | H&I | R&(~P)&I | F&P&(~I)]is non-zero, where:
The Switch8 Module supports both the standard shared commands and the shared interrupt commands in addition to the following commands:
Command Send/
ReceiveByte Value Discussion 7 6 5 4 3 2 1 0 Read Inputs Send 0 0 0 0 0 0 0 0 Return input values abcdefgh (after XOR'ing with complement mask) Receive a b c d e f g h Read Complement Mask Send 0 0 0 0 0 0 0 1 Return complement mask cccccccc Receive c c c c c c c c Read Low Mask Send 0 0 0 0 0 0 1 0 Return low mask llllllll Receive l l l l l l l l Read High Mask Send 0 0 0 0 0 0 1 1 Return high mask hhhhhhhh Receive h h h h h h h h Read Raising Mask Send 0 0 0 0 0 1 0 0 Return raising mask rrrrrrrr Receive r r r r r r r r Read Falling Mask Send 0 0 0 0 0 1 0 1 Return falling mask ffffffff Receive f f f f f f f f Read Raw Send 0 0 0 0 1 0 0 0 Return raw data abcd (without XOR'ing with complement mask) Receive a b c d e f g h Set Complement Mask Send 0 0 0 0 1 0 0 1 Set complement mask to cccccccc Send c c c c c c c c Set Low Mask Send 0 0 0 0 1 0 1 0 Set low mask to llllllll Send l l l l l l l l Set High Mask Send 0 0 0 0 1 0 1 1 Set high mask to hhhhhhhh Send h h h h h h h h Set Raising Mask Send 0 0 0 0 1 1 0 0 Set raising mask to rrrrrrrr Send r r r r r r r r Set Falling Mask Send 0 0 0 0 1 1 0 1 Set falling mask to ffffffff Send f f f f f f f f Read Interrupt Bits Send 1 1 1 0 1 1 1 1 Return the interrupt pending bit p and the interrupt enable bit e. Receive 0 0 0 0 0 0 e p Set Interrupt Commands Send 1 1 1 1 0 c c c Set Interrupt Command ccc. Shared Commands Send 1 1 1 1 1 c c c Execute Shared Command ccc.
The hardware consists of a circuit schematic and a printed circuit board.
The schematic for the Switch8 Module is shown below:
The parts list kept in a separate file -- switch8.ptl.
The printed circuit board files are listed below:
The Switch8 software is available as one of:
Any fabrication issues are listed here.