diff --git a/ACME_Lib/cbm/c128/kernal.a b/ACME_Lib/cbm/c128/kernal.a
index ad2fe18..085e933 100644
--- a/ACME_Lib/cbm/c128/kernal.a
+++ b/ACME_Lib/cbm/c128/kernal.a
@@ -13,8 +13,8 @@ lib_cbm_c128_kernal_a = 1
 	k_dma_call	= $ff50
 	k_boot_call	= $ff53
 	k_phoenix	= $ff56
-	k_lkupla	= $ff59
-	k_lkupsa	= $ff5c
+	k_lkupla	= $ff59	; find channel with file number A
+	k_lkupsa	= $ff5c	; find channel with secondary address Y
 	k_swapper	= $ff5f
 	k_dlchr		= $ff62
 	k_pfkey		= $ff65
diff --git a/ACME_Lib/cbm/c128/mmu.a b/ACME_Lib/cbm/c128/mmu.a
index ef714ea..ada28a9 100644
--- a/ACME_Lib/cbm/c128/mmu.a
+++ b/ACME_Lib/cbm/c128/mmu.a
@@ -71,13 +71,13 @@ mmu_CR_BANK15	= $00	; 16 KiB bank 0; 32 KiB basic; 16 KiB kernel with i/o overla
 	mmu_mcr		= $d505
 }
 ; contents:
-mmu_MCR_40COLUMNS	= %#.......	; 40/80 key: 0 means pressed, 1 means released (writable! if cleared, will always read as 0!)
-mmu_MCR_C64MODE		= %.#......	; setting this bit makes the MMU disappear from the memory map :)
-mmu_MCR_EXROM		= %..#.....	; if zero on boot, system will enter c64 mode (writable!)
-mmu_MCR_GAME		= %...#....	; if zero on boot, system will enter c64 mode (writable!)
-mmu_MCR_FSDIR_OUTPUT	= %....#...	; direction of fast serial bus
+mmu_MCR_40COLUMNS	= %#.......	; (pin 48) 40/80 key: 0 means pressed, 1 means released (writable! if cleared, will always read as 0!)
+mmu_MCR_C64MODE		= %.#......	; (pin 47) setting this bit makes the MMU disappear from the memory map :)
+mmu_MCR_EXROM		= %..#.....	; (pin 46) if zero on boot, system will enter c64 mode (writable!)
+mmu_MCR_GAME		= %...#....	; (pin 45) if zero on boot, system will enter c64 mode (writable!)
+mmu_MCR_FSDIR_OUTPUT	= %....#...	; (pin 44) direction of fast serial bus
 mmu_MCR_UNUSED		= %.....##.	; always set
-mmu_MCR_8502MODE	= %.......#	; setting this to zero switches to Z80 cpu
+mmu_MCR_8502MODE	= %.......#	; (pin 43 inverted) setting this to zero switches to Z80 cpu
 
 !address {
 	; ram configuration register
diff --git a/ACME_Lib/cbm/kernal.a b/ACME_Lib/cbm/kernal.a
index 1c5611b..46f2647 100644
--- a/ACME_Lib/cbm/kernal.a
+++ b/ACME_Lib/cbm/kernal.a
@@ -45,6 +45,6 @@ lib_cbm_kernal_a = 1
 	k_clall		= $ffe7
 	k_udtim		= $ffea
 	k_scrorg	= $ffed
-	k_plot		= $fff0	; get/set cursor (to set, clear carry)
+	k_plot		= $fff0:k_plot_CXY	= $fff0	; get/set cursor (to set, clear carry. X/Y are y/x!)
 	k_iobase	= $fff3
 }