List of Figures
82C836 CHIPSet Introduction
Figure 1-1.
SCATsx Basic System Architecture . . . . . . . . . . . . . . . . . . . . . . . 1-2
Pin Assignments
Figure 2-1.
160-Pin PFP Pinout (Top View) . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Functional Description
Figure 3-1.
Figure 3-2.
Figure 3-3.
Pull-Low Function----Alternate Implementation . . . . . . . . . . . . . . 3-2
PS Diode for External Real Time Clock Systems . . . . . . . . . . . . . 3-3
Battery Backup Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4
Clock/Bus Control
Figure 4-1.
Clock Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
System Interface
Figure 5-1.
Figure 5-2.
Figure 5-3.
Figure 5-4.
Figure 5-5.
Figure 6-1.
Figure 6-2.
Figure 6-3.
Figure 6-4.
Figure 6-5.
Figure 6-6.
Figure 6-7.
Figure 6-8.
Figure 6-9.
MRA Mode Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
Encoded RAS Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
Example of EMS/Extended Memory . . . . . . . . . . . . . . . . . . . . . . . 5-15
-READYO Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-17
Keyboard Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-18
Register A----Address 0AH (All Bits Except UIP are Read/Write) 6-4
Register B----Address 0BH (Read Only) . . . . . . . . . . . . . . . . . . . . 6-5
Register C----Address 0CH (Read Only) . . . . . . . . . . . . . . . . . . . . 6-6
Register D----Address 0DH (Read Only) . . . . . . . . . . . . . . . . . . . . 6-7
Update Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-8
Programmable Timer Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-9
Control Word----Address 043H . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-11
Read-Back Command Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-13
Status Byte Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-14
Interrupt Controller
Figure 7-1.
Figure 7-2.
Figure 7-3.
Figure 7-4.
Figure 7-5.
Figure 7-6.
Figure 7-7.
Figure 7-8.
Figure 7-9.
Figure 7-10.
Figure 7-11.
Figure 7-12.
Figure 7-13.
Figure 7-14.
Cascaded Interrupt Controllers . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2
Interrupt Controller Block Diagram . . . . . . . . . . . . . . . . . . . . . . . 7-3
Initialization Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
Fixed Priority Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6
Specific Rotation Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-7
Automatic Rotation Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-7
ICW1----Address 020H (0A0H) Write Only . . . . . . . . . . . . . . . . . 7-9
ICW2----Address 021H (0A1H) Write Only . . . . . . . . . . . . . . . . . 7-10
ICW3 Format for INTC1 ----Address 021H Write Only . . . . . . . . . 7-10
ICW3 Format for INTC2 ----Address 0A1H Write Only . . . . . . . . 7-10
ICW4----Address 021H (0A1H) Write Only . . . . . . . . . . . . . . . . . 7-11
OCW----Address 021H (0A1H) Read/Write . . . . . . . . . . . . . . . . . 7-12
OCW2----Address 020H (0A0H) Write Only . . . . . . . . . . . . . . . . 7-13
OCW3----Address 020H (0A0H) Write Only . . . . . . . . . . . . . . . . 7-14
DMA Controller
Figure 8-1.
Figure 8-2.
Figure 8-3.
Figure 8-4.
Cascaded DMA Controllers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
Command Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10
Mode Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-11
Request Register (Write Operaton) . . . . . . . . . . . . . . . . . . . . . . . . 8-12
82C836 CHIPSet Data Sheet
Contents
I
Chips and Technologies, Inc.
P R E L I M I N A R Y
Revision 3.0
ix