From 17c25a1029ef00ea6fd63455b51fe58b28552f78 Mon Sep 17 00:00:00 2001
From: stefan-b-jakobsson
 <70063525+stefan-b-jakobsson@users.noreply.github.com>
Date: Thu, 22 Aug 2024 23:02:06 +0300
Subject: [PATCH] [KERNAL] Num Lock as first keystroke fix (#354)

* [KERNAL] enable control and persisting of ps2kbd LED state, respond to numlock

* extapi setter must use .X, and for consistency change getter

* Check command status before sending set LED status command

---------

Co-authored-by: mooinglemur <mooinglemur@users.noreply.github.com>
---
 kernal/drivers/x16/ps2kbd.s | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/kernal/drivers/x16/ps2kbd.s b/kernal/drivers/x16/ps2kbd.s
index 95bda023..d7376cc8 100644
--- a/kernal/drivers/x16/ps2kbd.s
+++ b/kernal/drivers/x16/ps2kbd.s
@@ -39,7 +39,9 @@
 I2C_ADDRESS = $42
 I2C_KBD_ADDRESS = $43
 I2C_GET_SCANCODE_OFFSET = $07
+I2C_GET_KBD_CMD_STATUS = $18
 I2C_KBD_CMD2 = $1a
+I2C_CMD_PENDING = $01
 
 MODIFIER_SHIFT = 1 ; C64:  Shift
 MODIFIER_ALT   = 2 ; C64:  Commodore
@@ -594,6 +596,12 @@ kbd_leds:
 
 _set_kbd_leds:
 	ldx #I2C_ADDRESS
+	ldy #I2C_GET_KBD_CMD_STATUS
+:	jsr i2c_read_byte
+	cmp #I2C_CMD_PENDING
+	beq :-
+
+	; Set LED state command
 	ldy #I2C_KBD_CMD2
 	lda #$ed
 	jsr i2c_write_first_byte