Z16M1720ASG1868 Zilog, Z16M1720ASG1868 Datasheet - Page 113

• Manufacturer Part Number: Z16M1720ASG1868
• Description: IC PCMCIA INTERFACE 100-VQFP
• Manufacturer: Zilog

Specifications of Z16M1720ASG1868

• Applications: *
• Interface: *
• Voltage - Supply: *
• Package / Case: 100-LQFP
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

UM008101-0601
Figure 40.
Block Length
All operations must have a declared block length because the default values
at power-up are unpredictable for block length. These registers are written
to by setting pointer bits 5 and 6 in the WR0 base register byte. The block
length can be up to 64 Kbytes. Due to the pipelining method of reading in
data, the number of bytes actually searched or transferred may be one or
two more than the number entered here. “Address and Byte Counting” on
page 75 in “Internal Structure” on page 71 describes this (Table 11).
Programming a block length of zero results in the transfer or search of 216
+ 1 bytes. Therefore, the shortest block length that can be entered is 1,
which usually results in a transfer or search of two bytes (Table 12).
D7 D6 D5 D4 D3 D2 D1 D0
Write Register 0 Group
0 = Port B
0 = Port A
0
0
1
1
0
1
0
1
= Transfer
= Search
= Search/Transfer
→
→
Base Register Byte
Port A starting address (Low Byte)
Port A starting address (High Byte)
Block length (Low Byte)
Block length (High Byte)
Do not use
Port A
Port B
<   % 2 7 2 G T K R J G T C N U
Direct Memory Access
7 U G T / C P W C N