“QMK” – Keyboard controller (RP2354A)

CPU overclocked from (1x) 150Mhz (1.1v) to (2x) 300Mhz (1.2v), possibly to (3x) 460Mhz (1.5v) – other have driven the RP2350/4A to over 600Mhz (2v).

QMK has 2MB flash built-in and no ps-ram. Pin 8 is used for FRAM access.

The SticKey USB port is directly connected to the official keyboard:

The prototype will use an AJAZZ AK820 (wired) 75% 82 key (83 as the rotary knob has a button) RGB keyboard with rotary control.

If all goes to plan, there will be a custom keyboard with the same layout as the AK820, but using a RP234A as the keyboard controller. This should allow the ability to use standard QMK firmware. The DeMon chip can reset and reprogram the keyboard with new firmware as needed.

Row to column, Schottkey diodes will have to be used for fast sampling.

FRAM16 map (000000-FFFFFF)

Start address	End address	Size	Description
000000	3FFFFF	400000	4MB SRAM
040000	7FFFFF	400000	Reserved

GPIO	Function	GPIO	Function
0	PWM0A buzzer L	20	COL 5
1	RGBW out	21	COL 6
2	PWM1A buzzer R	22	COL 7
3	Caps locK	23	COL 8
4	I2C0 SDA CAT24C512 64K byte EEPROM	24	COL 9
5	I2C0 SCL	25	COL A
6	ENCODER A (jog dial)	26	COL B
7	ENCODER B	27	COL C
8	FRAM CS1n	28	COL D
9	ROW 0	29	COL E
10	ROW 1	SWDIO	Connected to DeMon to
11	ROW 2	SWDCLK	allow debug/programming
12	ROW 3	ADCREF
13	ROW 4	3V3
14	ROW 5	BOOTSEL
15	COL 0	USB D-	Internal keyboard USB master port
16	COL 1	USB D+
17	COL 2	RUN	Connected to DeMon
18	COL 3	3V3 EN
19	COL 4	VBUS