From f2eead4db8f0f010e94b1308dedf0320c9cbced4 Mon Sep 17 00:00:00 2001 From: Dave Date: Wed, 15 Apr 2020 15:23:42 -0500 Subject: [PATCH] Updated README to reflect progress --- firmware/asdf/README.md | 31 +++++++++++++++++++++---------- 1 file changed, 21 insertions(+), 10 deletions(-) diff --git a/firmware/asdf/README.md b/firmware/asdf/README.md index 2f1d702..4fa31c3 100644 --- a/firmware/asdf/README.md +++ b/firmware/asdf/README.md @@ -22,13 +22,13 @@ Features: -- * modifiers: A set of modifier keys may be specified. When only a few modifiers are used, this mechanism is a low-overhead alternative to a keymap overlay for - keyboard states that only change the key value, such as SHIFT, CAPS LOCK, CONTROL, - etc. The state of each modifier key is kept in a state variable. In most - cases, pressing the key will set the value to a "pressed" state, and releasing - will reset the value to an "unpressed" state. However some functions interact. - For example, Shift Lock is sticky, so pressing Shift Lock toggles the Shift - Lock state, and Releasing Shift Lock does nothing; but pressing "Shift" will - reset the "Shift Lock" state. + keyboard states that only change the key codes produced by a keypress, such as + SHIFT, CAPS LOCK, CONTROL, etc. The state of each modifier key is kept in a + state variable. In most cases, pressing the key will set the value to a + "pressed" state, and releasing will reset the value to an "unpressed" state. + However some functions interact. For example, Shift Lock is sticky, so + pressing Shift Lock toggles the Shift Lock state, and Releasing Shift Lock + does nothing; but pressing "Shift" will reset the "Shift Lock" state. All modifier state variables are kept in a modifier state variable array. On a regular keypress, all of the modifier state variables are OR'ed together to @@ -46,6 +46,7 @@ Features: * (1): ADM-style ASCII keyboard (all caps) * (2): Apple 2 ASCII keyboard (upper/lower) * (3): Apple 2 ASCII keyboard (standard all caps) + * (4): Sol-20 ASCII keyboard * Debounce and Repeat functions: The main keyscan logic implements key debouncing. Multiple keys may be debounced simultaneously using a separate @@ -78,7 +79,7 @@ Porting This firmware was written in modular, portable C99, to be compiled with GCC (avr-gcc for the Atmega). The hardware-sepecific files are in Arch/*.[ch]. To adapt the Atmega port for additional hardware, enter the ./src/Arch directory, -and copy the files asdf_arch_atmega328p.c and asdf_arch_astmega328p.h to new +and copy the files asdf_arch_atmega2560.c and asdf_arch_astmeg2560.h to new filenames, and edit them to suit the hardware changes. The firmware is designed to run from ROM on a slow vintage processor, with a @@ -90,7 +91,7 @@ The code was written to favor readability over cleverness. While tempted to optimize bit testing via bithacks, I opted for code simplicity since the performance benefit was not there for 8-bit values. -To port to a new processor architecture, you may use the atmega328p files as an +To port to a new processor architecture, you may use the atmega2560 files as an example, and create a pair of architecture-specific .c and .h files for the new hardware, exporting the following functions: @@ -109,5 +110,15 @@ hardware, exporting the following functions: that case, this function is not needed, and the "superloop" in main.c would contain a call to the scheduler. -- asdf_arch_XXXX_set: The hardware provides a number of physical resources, such as TTL or tri-state outputs, which can be used to drive LEDs, TTL logic output lines, etc. These are driven by a virtual output layer. The virtual layer requires a function to set the state of the physical resources. One function is provided for each such resource. For example, if a TTL output is called OUT1, then the function asdf_arch_out1_set() must be defined. +- asdf_arch_XXXX_set: The hardware provides a number of physical resources, such + as TTL or tri-state outputs, which can be used to drive LEDs, TTL logic output + lines, etc. These are driven by a virtual output layer. The virtual layer + requires a function to set the state of the physical resources. One function + is provided for each such resource. For example, if a TTL output is called + OUT1, then the function asdf_arch_out1_set() must be defined. For now, the + required devices are: +- LED1, LED2, LED3 (LED outputs) +- OUT1, OUT2, OUT3 (TTL outputs) +- OUT1\_OPEN\_HI, OUT2\_OPEN\_HI, OUT3\_OPEN\_HI (Open collector outputs) +- OUT1\_OPEN\_LO, OUT2\_OPEN\_LO, OUT3\_OPEN\_LO (Open emitter outputs)