;
; 6522 (VIA) registers
;

            .virtual
_via            .struct
iorb                    .byte ?
iora                    .byte ?
ddrb                    .byte ?
ddra                    .byte ?
t1c                     .word ?
t1l                     .word ?
t2c                     .word ?
sr                      .byte ?
acr                     .byte ?
pcr                     .byte ?
ifr                     .byte ?
ier                     .byte ?
ioran                   .byte ?
                .endstruct
            .endvirtual

VIA_SR_OFF              = 0 << 2
VIA_SR_IN_T2            = 1 << 2
VIA_SR_IN_CLOCK         = 2 << 2
VIA_SR_IN_EXT           = 3 << 2
VIA_SR_OUT_T2_FR        = 4 << 2
VIA_SR_OUT_T2_CB1       = 5 << 2
VIA_SR_OUT_CLOCK        = 6 << 2
VIA_SR_OUT_EXT          = 7 << 2

; vim: syntax=64tass