Micrel, Inc.
MIC2555
Interrupt Source Register
Indicates the current state of signals that can
generate an interrupt.
Interrupt Status
rd - 08h
bit 0
1 = VBUS > 4.4V
vbus_vld
sess_vld
1
1
rd
rd
(VBUS valid comparator)
1 = 0.8V< VBUS< 2.0V.
(Session valid comparator)
1 = D+ pin is HIGH
1 = ID pin grounded
1 = D- pin is HIGH
bit 1
se_dp
1
1
1
1
rd
rd
rd
rd
bit 2
bit 3
bit 4
bit 5
id_gnd_in
se_dm
id_float
1 = ID pin floating
If: bdis_acon_en = 1
1 = SE0 has been detected, transceiver asserted
dp_pullup after detecting B-device disconnect.
bdis_acon
(sess_end)
1
1
rd
rd
bit 6
bit 7
If bdis_acon_en = 0, sess_end_en = 1
1 = VBUS < 0.8V. (Session End comparator output =
TRUE)
1 = car kit interrupt, D+ pin has seen a pulse above
the interrupt level
cr_int
Interrupt Latch 1
set –0Ah
clr – 0Bh
bit 0
Indicates which sources have interrupted. 1 =
interrupt.
Interrupt Source
Vbus_vld
sess_vld
se_dp
1
1
1
1
1
1
rd/s/c
rd/s/c
rd/s/c
rd/s/c
rd/s/c
rd/s/c
bit 1
bit 2
id_gnd_in
se_dm
bit 3
bit 4
id_float
bit 5
bdis_acon
(sess_end)
1
1
rd/s/c
rd/s/c
bit 6
bit 7
cr_int
Interrupt Mask False
Enables interrupts on transition from TRUE to FALSE
1 Æset = 1, Interrupt on TÆF.
1 Æclr = 0, no interrupt.
set – 0Ch
clr – 0Dh
False
Interrupt Mask
Vbus_vld
sess_vld
se_dp
1
1
1
1
1
1
rd/s/c
rd/s/c
rd/s/c
rd/s/c
rd/s/c
rd/s/c
bit 0
bit 1
bit 2
bit 3
bit 4
bit 5
id_gnd_in
se_dm
id_float
bdis_acon
(sess_end)
1
1
rd/s/c
rd/s/c
bit 6
bit 7
cr_int
M9999-060805
(408) 955-1690
June 2005
24
MICREL [ MICREL SEMICONDUCTOR ]
