di0ib
/
keybrd
Watch 1
Star 0
Fork 0
Code Releases 7 Activity
Browse Source

document

tags/v0.6.3
wolfv6 7 years ago
parent
ce9c10aba6
commit
e84db1c61c
6 changed files with 51 additions and 44 deletions
Split View Show Diff Stats
  1. 4
    11
      CONTRIBUTING.md
  2. 3
    3
      doc/PLANNED_FEATURES.md
  3. 21
    15
      src/Scanner_ShiftRegsRead.h
  4. 21
    13
      src/Scanner_ShiftRegsReadStrobed.h
  5. 1
    1
      tutorials/tutorial_4_connecting_split_keyboards.md
  6. 1
    1
      tutorials/tutorial_4b_split_keyboard_with_shift_registers.md

+ 4
- 11
CONTRIBUTING.md View File

@@ -36,6 +36,10 @@ Code contributions
Unsure of where to begin contributing to keybrd code?
You can start by looking through the improvement suggestions, bug reports, and [planned_features](doc/planned_features.md).
Scratch your own itch. Code for your own need. Then share it with the keybrd community.
* [Tutorial 8b - sharing your keybrd extension library](tutorials/tutorial_8b_sharing_your_keybrd_extension_library.md)
* [Tutorial 8c - sharing your keybrd sketch](tutorials/tutorial_8c_sharing_your_keybrd_sketch.md)
Git commit message style guide:
* Limit the first line to 72 characters summary
* Second line should be empty, followed by body of the commit message
@@ -95,17 +99,6 @@ If you prefer your answers remain confidential, pm the completed Q & A to [wolfv
Usability survey results will be used to make improvements to the keybrd library.
### Schematics
The most glaring deficiency is the tutorials' lack of schematics.
Schematics would be easier to read than the current photos.
Schematics are not my area of expertise. Use what ever would be the best solution for the tutorials:
* schematics
* breadboard drawings
* Arduino simulation software
Contributions of tutorial schematics would benefit users new to the keybrd library.
### Documentation
Suggest a clarification, simplification, correction, or other improvement.
We need the perspective of people new to the project to see these things.

+ 3
- 3
doc/PLANNED_FEATURES.md View File

@@ -2,12 +2,12 @@ planned_features is a view of where the keybrd project is headed.
Top priority
------------
* User testing
* Add matrix-to-layout mapping (to decouple key matrix from layout)
* Add breadboard keyboard schematics to tutorials
Medium priority
---------------
* Add matrix-to-layout mapping (to decouple key matrix from layout)
* Add breadboard keyboard schematics to tutorials
* Getting user feedback
Low priority
------------

+ 21
- 15
src/Scanner_ShiftRegsRead.h View File

@@ -1,5 +1,5 @@
#ifndef ROWSCANNER_SHIFTREGSPISOSINGLEROW_H
#define ROWSCANNER_SHIFTREGSPISOSINGLEROW_H
#ifndef ROWSCANNER_SHIFTREGSREAD_H
#define ROWSCANNER_SHIFTREGSREAD_H

#include <Arduino.h>
#include <inttypes.h>
@@ -8,29 +8,33 @@
#include <ScannerInterface.h>

/* Scanner_ShiftRegsRead reads shift registers.
This was tested on 74HC165 shift registers, which are Parallel-In-Serial-Out (PISO).
Upto 4 shift registers can be in a daisy chained for a total of 32 read pins.
This was tested on 74HC165 shift registers, which are Parallel-In-Serial-Out (PISO).

The row is always powered (there is no strobe that turns off).

Example instantiation:
Row row_R0(scanner_R, 0, ptrsKeys_R0, sizeof(ptrsKeys_R0)/sizeof(*ptrsKeys_R0));
Scanner_ShiftRegsRead scanner_R(HIGH, SS, 4);
Scanner_ShiftRegsRead scanner_R(HIGH, 6, 4);

The Row "strobePin" parameter is ignored.
In the above example, the "strobePin" argument is 0, but it doesn't matter what value is given.
In the above Row instantiation, argument 0 for "strobePin" is ignored because there is no strobe.

There are three Scanner_ShiftRegsRead parameters.
"strobeOn" paramter is ignored, but should be active state HIGH or LOW required by ScannerInterface.

"slaveSelect" paramter can be any controller pin connected to shift register's SHIFT-LOAD pin.

"byte_count" is the number of bytes to read from shift registers (1 to 4).
byte_count should cover all the row's keys:
byte_count*8 >= row's keyCount
1. "strobeOn" paramter is ignored, but should be active state HIGH or LOW for ScannerInterface.
2. "slaveSelect" paramter can be any controller pin connected to shift register's SHIFT-LOAD pin.
3. "byte_count" is the number of bytes to read from shift registers (1 to 4).
byte_count should cover all the row's keys: byte_count*8 >= row's keyCount

Hardware setup:
There is only one row, and it is permanently active.
The row of keys is connected to a controller by 5 wires:
* GND
* power
* CLK
* Slave Select
* MISO

Switches are connected to shift-register parallel-input pins and row.
Diodes are not needed because there is only one row.
Diodes are not needed if there is only one row.

For active low:
Shift-register parallel-input pins need 10k Ohm pull-up resistors powered.
@@ -41,6 +45,8 @@ For active high:
Shift-register parallel-input pins need 10k pull-down resistors grounded.
Switches connect grouned row to parallel-input pins.
Controller's MISO pin is connected to shift register's serial output (QH) pin

If multiple rows (or any SPI divice) share a MISO line, the shift registers need to be isolated by a tri-state buffer chip.
*/
class Scanner_ShiftRegsRead : public ScannerInterface
{

+ 21
- 13
src/Scanner_ShiftRegsReadStrobed.h View File

@@ -1,5 +1,5 @@
#ifndef ROWSCANNER_SHIFTREGSPISOMULTIROW_H
#define ROWSCANNER_SHIFTREGSPISOMULTIROW_H
#ifndef ROWSCANNER_SHIFTREGSREADSTROBED_H
#define ROWSCANNER_SHIFTREGSREADSTROBED_H

#include <Arduino.h>
#include <inttypes.h>
@@ -8,24 +8,30 @@
#include <ScannerInterface.h>

/* Scanner_ShiftRegsReadStrobed reads shift registers.
This was tested on 74HC165 shift registers, which are Parallel-In-Serial-Out (PISO).
Shift registers can be daisy chained for a total of 32 read pins.
This was tested on 74HC165 shift registers, which are Parallel-In-Serial-Out (PISO).

The class works with machanical switches or photointerrupter switches.
A "strobe" powers the IR LEDs for a short time while the shift registers read the photo transistors.
The IR LEDs are off most of the time to preserve IR LED life.

Example instantiation:
Scanner_ShiftRegsReadStrobed scanner_R(HIGH, SS, 4);
Scanner_ShiftRegsReadStrobed scanner_R(HIGH, 6, 4);

There are three Scanner_ShiftRegsReadStrobed parameters.
"strobeOn" paramter is active state HIGH or LOW.

"slaveSelect" paramter can be any controller pin connected to shift register's SHIFT-LOAD pin.

"byte_count" is the number of bytes to read from shift registers (1 to 4).
byte_count should cover all the row's keys:
byte_count*8 >= row's keyCount
1. "strobeOn" paramter is active state HIGH or LOW.
2. "slaveSelect" paramter is controller pin connected to shift register's SHIFT-LOAD pin.
3. "byte_count" is the number of bytes to read from shift registers (1 to 4).
byte_count should cover all the row's keys: byte_count*8 >= row's keyCount

Hardware setup:
Each row needs to be connected to a strobe pin from the controller.
Switch and diode in series, connect shift-register parallel-input pins to strobed row.
Each row of keys is connected to a controller by 6 wires:
* GND
* power
* CLK
* Slave Select
* MISO
* strobe

For active low:
Shift-register parallel-input pins need 10k Ohm pull-up resistors powered.
@@ -36,6 +42,8 @@ For active high:
Shift-register parallel-input pins need 10k pull-down resistors grounded.
Orient diodes with cathode (banded end) towards the read pins.
Controller's MISO pin is connected to shift register's serial output (QH) pin

If multiple rows (or any SPI divice) share a MISO line, the shift registers need to be isolated by a tri-state buffer chip.
*/
class Scanner_ShiftRegsReadStrobed : public ScannerInterface
{

+ 1
- 1
tutorials/tutorial_4_connecting_split_keyboards.md View File

@@ -49,7 +49,7 @@ More scanning options are reviewed at http://www.openmusiclabs.com/learning/digi

Only ready-made cables that are widely available are listed.
There are hundreds of other connectors listed at http://pinouts.ru/
There are also wireless options if you don't mind adding complexity and maintaining a battery.
There are also wireless options at the expense of adding complexity and maintaining a battery.

The 8-wire "GearIT Cat 6 Ethernet Flat Patch Cable 7 Feet" is very flexible.
It's available at Walmart (9/19/16) if you want to feel the merchandise before you buy.

+ 1
- 1
tutorials/tutorial_4b_split_keyboard_with_shift_registers.md View File

@@ -3,7 +3,7 @@ keybrd Tutorial 4b - split keyboard with shift registers
When you finish this tutorial you will be able to be able to modify a split keybrd sketch with 10 to 24 keys on the shift registers.

Overview of split keyboard with shift registers
------------------------------------------------
-----------------------------------------------
The breadboard in the following picture models a split keyboard.
The green rectangle on the left is a Teensy LC micro controller.
The black rectangles in the middle are two SN74HC165N shift registers daisy chained together.