
CHAPTER 1 INTRODUCTION
4
The keyboard interface unit (KIU) has 8 scan lines and as many detection lines. It can detect when any
of 64 keys are pressed. It supports key rollover for two to three continuous strokes.
(12) Touch panel interface unit (PIU)
The touch panel interface unit (PIU) detects when the touch panel is touched. The current V
R
4101
version supports interfaces for two A/D converters, TLC2543C and TLV1543C.
(13) Debug serial interface unit (Debug SIU)
The debug serial interface unit (debug SIU) is a serial interface for debugging. It supports a maximum
transfer rate of 115 kbps.
(14) Serial interface unit (SIU)
The serial interface unit (SIU) complies with the RS-232-C specification. It supports a maximum
transfer rate of 115 kbps. Also available is an IrDA serial interface supporting a maximum transfer rate
of 115 kbps, but this interface and the RS-232-C interface are mutually exclusive.
1.4.2 I/O registers
The I/O registers are used for peripheral unit control. The I/O registers are listed below.
Table 1-1. BCU Registers
Name
Function
Address
BCUCNTREG
BCU Control register
0x0B00 0000
BCUBRREG
BCU Bus Restrain register
0x0B00 0002
BCUBRCNTREG
BCU Bus Restrain Count register
0x0B00 0004
BCUBCLREG
BCU CPU Restrain Disable register
0x0B00 0006
BCUCLCNTREG
BCU CPU Restrain Disable Count register
0x0B00 0008
BCUSPEEDREG
BCU Access Cycle Change register
0x0B00 000A
BCUERRSTREG
BCU Bus Error Status register
0x0B00 000C
BCURFCNTREG
BCU Refresh Control register
0x0B00 000E
PREVIDREG
Peripheral Revision ID register
0x0B00 0010