Z80 Datasheet, PDF (11/330 Pages) Zilog, Inc. – Z80 CPU PERIPHERALS

Z80 CPU Peripherals
User Manual
xi
Direct Memory Access (continued)
Figure 50. CE/WAIT Multiplexer . . . . . . . . . . . . . . . . . . . . . . . . . . .133
Figure 51. Simultaneous Transfer Multiplexer . . . . . . . . . . . . . . . . .133
Figure 52. Simultaneous Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . .134
Figure 53. Delaying the Leading Edge of MWR . . . . . . . . . . . . . . . .135
Figure 54. Data Bus Buffer Control Example . . . . . . . . . . . . . . . . . .138
Figure 55. DMA-SIO Environment . . . . . . . . . . . . . . . . . . . . . . . . . .142
Figure 56. Connecting DMA to Demultiplexed Address/Data Buses 145
Figure 57. Z8000/Z80 Peripheral Interface . . . . . . . . . . . . . . . . . . . .147
Figure 58. DMA Bus-Master Gate (Byte or Burst Modes Only) . . . .149
Figure 59. CPU-to-DMA Write Cycle Requirements . . . . . . . . . . . .151
Figure 60. CPU-to-DMA Read Cycle Requirements . . . . . . . . . . . . .152
Figure 61. Sequential Memory-to-I/O Transfer, Standard Timing
(Searching is Optional) . . . . . . . . . . . . . . . . . . . . . . . . . . .154
Figure 62. Sequential I/O-to-Memory Transfer, Standard Timing
(Searching is Optional) . . . . . . . . . . . . . . . . . . . . . . . . . . .155
Figure 63. Simultaneous Memory-to-I/O Transfer (Burst and Continuous
Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .156
Figure 64. Simultaneous Memory-to-I/O Transfer (Byte Mode) . . . .157
Figure 65. Bus Request and Acceptance Timing . . . . . . . . . . . . . . . .159
Figure 66. Bus Release in Byte Mode . . . . . . . . . . . . . . . . . . . . . . . .160
Figure 67. Bus Release on End-of-Block (Burst and
Continuous Modes) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .160
Figure 68. Bus Release on Match (Burst and Continuous Modes) . .161
Figure 69. Bus Release on Not Ready (Burst Mode) . . . . . . . . . . . . .162
Figure 70. RDY Line in Byte Mode . . . . . . . . . . . . . . . . . . . . . . . . . .163
Figure 71. RDY Line in Burst Mode . . . . . . . . . . . . . . . . . . . . . . . . .164
Figure 72. RDY Line in Continuous Mode . . . . . . . . . . . . . . . . . . . .165
Figure 73. Variable-Cycle and Edge Timing . . . . . . . . . . . . . . . . . . .166
List of Figures
UM008101-0601