[KERNAL] remove the infinite spinlock on setting the kbd LEDs and def…

…er to next tick (X16Community#365)

kernal/drivers/x16/ps2data.s

@@ -20,7 +20,7 @@ PS2DATA_NEW_STYLE = $02
 LED_NUM_LOCK	= 2
 
 .import i2c_read_byte, i2c_read_first_byte, i2c_direct_read, i2c_read_next_byte, i2c_read_stop, i2c_write_byte
-.import tpmflg, tpmcache, ledstate
+.import tpmflg, tpmcache, ledstate, leds_pending
 
 .export ps2data_init, ps2data_fetch, ps2data_kbd, ps2data_kbd_count, ps2data_mouse, ps2data_mouse_count
 .export ps2data_keyboard_and_mouse, ps2data_keyboard_only, ps2data_raw
@@ -55,6 +55,9 @@ ps2data_init:
 	lda #LED_NUM_LOCK
 	sta ledstate
 
+	; Clear flag for pending LED state change
+	stz leds_pending
+
 	; Compare SMC firmare version major
 	ldx #I2C_ADDR
 	ldy #CMD_GET_VER1

kernal/drivers/x16/ps2kbd.s

@@ -32,7 +32,7 @@
 
 .export kbd_config, kbd_scan, receive_scancode_resume, keymap, ps2kbd_typematic
 .export kbd_leds
-.export tpmflg, tpmcache, ledstate
+.export tpmflg, tpmcache, ledstate, leds_pending
 
 .import extapi
 
@@ -43,6 +43,8 @@ I2C_GET_KBD_CMD_STATUS = $18
 I2C_KBD_CMD2 = $1a
 I2C_CMD_PENDING = $01
 
+PS2_CMD_SET_LEDS = $ed
+
 MODIFIER_SHIFT = 1 ; C64:  Shift
 MODIFIER_ALT   = 2 ; C64:  Commodore
 MODIFIER_CTRL  = 4 ; C64:  Ctrl
@@ -80,6 +82,8 @@ dk_scan:
 	.res 1
 tpmcache:
 	.res 1
+leds_pending:
+	.res 1
 
 
 .segment "KEYMAP"
@@ -278,6 +282,10 @@ _kbd_scan:
 	jsr fetch_key_code
 	ora #0
 	bne @1
+	lda leds_pending
+	beq @0
+	jmp _set_kbd_leds
+@0:
 	rts			; No key
 
 	; Set typematic rate/delay on first keycode
@@ -598,17 +606,21 @@ kbd_leds:
 _set_kbd_leds:
 	ldx #I2C_ADDRESS
 	ldy #I2C_GET_KBD_CMD_STATUS
-:	jsr i2c_read_byte
+	jsr i2c_read_byte
 	cmp #I2C_CMD_PENDING
-	beq :-
+	beq @2
 
+	stz leds_pending
 	; Set LED state command
 	ldy #I2C_KBD_CMD2
-	lda #$ed
+	lda #PS2_CMD_SET_LEDS
 	jsr i2c_write_first_byte
 	lda ledstate
 	jsr i2c_write_next_byte
 	jmp i2c_write_stop
+@2:
+	sta leds_pending
+	rts
 
 ;*****************************************
 ; SET REPEAT RATE AND DELAY