Legacy-Free Keyboard/Embedded Controller with SPI and LPC Docking Interface
Table 13.17 Keyboard Scan-Out Register
N/A
HOST ADDRESS
8051 ADDRESS
0x7F04
(W)
VCC1
0x20
POWER
DEFAULT
BIT
D7
D6
D5
D4
D3
D2
D1
D0
-
-
-
-
-
-
-
-
HOST TYPE
8051 R/W
W
W
W
W
W
W
W
W
N/A
KSEN
1 =
D5 and D4 must be ‘0’
forces all D[3:0] = 0000 KSO[0] is asserted low
KSO
D[3:0] = 0001 KSO[1] is asserted low
lines to
go low
D[3:0] = 0010 KSO[2] is asserted low
D[3:0] = 0011 KSO[3] is asserted low
BIT NAME
.
.
.
D[3:0] = 1101 KSO[13] is asserted low
D[3:0] = 1110 KSO[14] is asserted low
D[3:0] = 1111 KSO[15] is asserted low
KSEN
1 = disable scanning of internal keyboard (all the KSOUT lines going high) (D4-D0 are don’t cares)
0 = enable scanning of internal keyboard
Note: Setting D[3:0] to 111x puts KSO0 - KSO13 outputs as Hi-Z.
Revision 1.1 (01-14-03)
152
SMSC LPC47N350
DATASHEET
SMSC [ SMSC CORPORATION ]
