FDC37N958FR Datasheet, PDF (185/316 Pages) List of Unclassifed Manufacturers – Notebook I/O Controller with Enhanced Keyboard and System Control

Direct Keyboard Scan
The FDC37N958FR scanning keyboard
controller is designed for intelligent keyboard
management in computer applications. By
properly configuring GPIO4 and GPIO5, the
FDC37N958FR may be programmed to directly
control keyboard interface matrixes of up to
16x8.
KEYBOARD SCAN-OUT REGISTER
Host
N/A
8051
0x7F04 (W)
Power
VCC1
Default
0x20
D7-D6 D5
D4
D3
D2 D1 D0
8051 R/W W
W
W
W
WWW
Bit Def
N/A KSEN 1 = forces D5 and D4 must be ‘0’
all KSO D[3:0] = 0000 KSO[0] is asserted low
lines to go D[3:0] = 0001 KSO[1] is asserted low
low
D[3:0] = 0010 KSO[2] is asserted low
D[3:0] = 0011 KSO[3] is asserted low
!
!
!
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: To support KSO14 and KSO15, GPIO4 and GPIO5 must be configured properly.
KEYBOARD SCAN-IN REGISTER
Host
N/A
8051
0x7F04 (R)
Power
VCC1
Default
N/A
D7-D0
8051 R
R
Bit description Reflects the state of KSI [7:0]
The value of the KSI[x] pins can be read through this register.
The pin values are latched during the read.
SMSC DS – FDC37N958FR
Page 179
Rev. 09/01/99