Motorola MC68VZ328 - Manual (Page 38)

1-8 MC68VZ328 User’s Manual
Modules of the MC68VZ328
1.3 Modules of the MC68VZ328
In addition to the powerful 68000 processor, the DragonBall VZ contains a wide variety of peripheral
interface and control modules. The following subsections provide brief descriptions of these modules and
how they operate.
1.3.1 Memory Controller
The memory controller provides a glueless interface to most memory chips on the market. It supports flash,
ROM, SRAM, different DRAM types (EDO RAM and Fast Page Mode), and synchronous DRAM. Either
one or two banks of DRAM may be used, and each bank can be a maximum of 32 Mbyte. For a more
complete explanation of how memory is configured and controlled, see Chapter 3, “Memory Map.”
1.3.2 Clock Generation Module and Power Control Module
The module containing the clock synthesizer operates with either an external crystal or an external
oscillator to provide a stable clock source for the internal clock generation module (CGM). The output
frequency can be adjusted by writing to the CGM frequency select register. The CGM can be disabled to
shut down the system clock divider chain for maximum power saving, while the real-time clock (RTC) and
DRAM controller remain active. The power control module can be configured to control the CPU cycles to
optimize power consumption. The power control module offers three power-saving modes: normal, doze,
EORI Exclusive OR immediate STOP Stop
EORI to CCR Exclusive OR immediate to condition codes SUB Subtract
EORI to SR Exclusive OR immediate to status register SUBA Subtract address
EXG Exchange registers SUBI Subtract immediate
EXT Sign extend SUBQ Subtract quick
JMP Jump SUBX Subtract with extend
JSR Jump to subroutine SWAP Swap data register halves
LEA Load effective address TAS Test and set operand
LINK Link stack TRAP Trap
LSL Logical shift left TRAPV Trap on overflow
LSR Logical shift right TST Test
MOVE Move UNLK Unlink
MOVEA Move address
Table 1-2. Instruction Set (Continued)
Mnemonic Description Mnemonic Description