diff --git a/asminc/vic20.inc b/asminc/vic20.inc
index d882eb1ad..a428ee76f 100644
--- a/asminc/vic20.inc
+++ b/asminc/vic20.inc
@@ -66,16 +66,43 @@ VIC_COLOR       := $900F        ; Border and background color
 ; ---------------------------------------------------------------------------
 ; I/O: 6522 VIA1
 
-VIA1            := $9110
-VIA1_JOY        := $9111
-VIA1_DDRB       := $9112
-VIA1_DDRA       := $9113
+VIA1            := $9110        ; *** Deprecated ***
+VIA1_JOY        := $9111        ; *** Deprecated ***
+VIA1_PB         := $9110        ; Port register B
+VIA1_PA1        := $9111        ; Port register A
+VIA1_DDRB       := $9112        ; Data direction register B
+VIA1_DDRA       := $9113        ; Data direction register A
+VIA1_T1CL       := $9114        ; Timer 1, low byte
+VIA1_T1CH       := $9115        ; Timer 1, high byte
+VIA1_T1LL       := $9116        ; Timer 1 latch, low byte
+VIA1_T1LH       := $9117        ; Timer 1 latch, high byte
+VIA1_T2CL       := $9118        ; Timer 2, low byte
+VIA1_T2CH       := $9119        ; Timer 2, high byte
+VIA1_SR         := $911A        ; Shift register
+VIA1_CR         := $911B        ; Auxiliary control register
+VIA1_PCR        := $911C        ; Peripheral control register
+VIA1_IFR        := $911D        ; Interrupt flag register
+VIA1_IER        := $911E        ; Interrupt enable register
+VIA1_PA2        := $911F        ; Port register A w/o handshake
 
 ; ---------------------------------------------------------------------------
 ; I/O: 6522 VIA2
 
-VIA2            := $9120
-VIA2_JOY        := $9120
-VIA2_DDRB       := $9122
-VIA2_DDRA       := $9123
-
+VIA2            := $9120        ; *** Deprecated ***
+VIA2_JOY        := $9120        ; *** Deprecated ***
+VIA2_PB         := $9120        ; Port register B
+VIA2_PA1        := $9121        ; Port register A
+VIA2_DDRB       := $9122        ; Data direction register B
+VIA2_DDRA       := $9123        ; Data direction register A
+VIA2_T1CL       := $9124        ; Timer 1, low byte
+VIA2_T1CH       := $9125        ; Timer 1, high byte
+VIA2_T1LL       := $9126        ; Timer 1 latch, low byte
+VIA2_T1LH       := $9127        ; Timer 1 latch, high byte
+VIA2_T2CL       := $9128        ; Timer 2, low byte
+VIA2_T2CH       := $9129        ; Timer 2, high byte
+VIA2_SR         := $912A        ; Shift register
+VIA2_CR         := $912B        ; Auxiliary control register
+VIA2_PCR        := $912C        ; Peripheral control register
+VIA2_IFR        := $912D        ; Interrupt flag register
+VIA2_IER        := $912E        ; Interrupt enable register
+VIA2_PA2        := $912F        ; Port register A w/o handshake