xii
17.2.2 Keyboard Control Register L (KBCRL).............................................................. 536
17.2.3 Keyboard Data Buffer Register (KBBR) ............................................................. 538
17.2.4 Module Stop Control Register (MSTPCR).......................................................... 538
17.3 Operation ........................................................................................................................... 539
17.3.1 Receive Operation................................................................................................ 539
17.3.2 Transmit Operation .............................................................................................. 541
17.3.3 Receive Abort....................................................................................................... 544
17.3.4 KCLKI and KDI Read Timing............................................................................. 547
17.3.5 KCLKO and KDO Write Timing......................................................................... 547
17.3.6 KBF Setting Timing and KCLK Control ............................................................. 548
17.3.7 Receive Timing.................................................................................................... 549
17.3.8 KCLK Fall Interrupt Operation............................................................................ 550
17.3.9 Usage Note ........................................................................................................... 551
Section 18A Host Interface
X-Bus Interface (XBS)
.............................................................................. 553
18A.1 Overview.......................................................................................................................... 553
18A.1.1 Features ............................................................................................................ 553
18A.1.2 Block Diagram.................................................................................................. 554
18A.1.3 Input and Output Pins....................................................................................... 555
18A.1.4 Register Configuration ..................................................................................... 556
18A.2 Register Descriptions........................................................................................................ 557
18A.2.1 System Control Register (SYSCR).................................................................. 557
18A.2.2 System Control Register 2 (SYSCR2) ............................................................. 558
18A.2.3 Host Interface Control Register (HICR) .......................................................... 559
18A.2.4 Input Data Register (IDR)................................................................................ 561
18A.2.5 Output Data Register (ODR)............................................................................ 561
18A.2.6 Status Register (STR)....................................................................................... 562
18A.2.7 Module Stop Control Register (MSTPCR)...................................................... 564
18A.3 Operation.......................................................................................................................... 564
18A.3.1 Host Interface Activation ................................................................................. 564
18A.3.2 Control States ................................................................................................... 566
18A.3.3 A20 Gate .......................................................................................................... 566
18A.3.4 Host Interface Pin Shutdown Function ............................................................ 568
18A.4 Interrupts .......................................................................................................................... 570
18A.4.1 IBF1, IBF2, IBF3, IBF4................................................................................... 570
18A.4.2 HIRQ11, HIRQ1, HIRQ12, HIRQ3, and HIRQ4............................................ 570
18A.5 Usage Note ....................................................................................................................... 572
Section 18B
Host Interface
LPC Interface (LPC)
.................................................................................. 573
18B.1 Overview.......................................................................................................................... 573
18B.1.1 Features ............................................................................................................ 573