ez80f91 ZiLOG Semiconductor, ez80f91 Datasheet - Page 73
![no-image](/images/no-image-200.jpg)
ez80f91
Manufacturer Part Number
ez80f91
Description
Ez80 Acclaimplus!? Connectivity Assp Ez80f91 Assp
Manufacturer
ZiLOG Semiconductor
Datasheet
1.EZ80F91.pdf
(387 pages)
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
ez80f917050SBCG
Manufacturer:
Zilog
Quantity:
135
Company:
Part Number:
ez80f91AZ050SG
Manufacturer:
Zilog
Quantity:
158
Part Number:
ez80f91NA050SG
Manufacturer:
ZILOG
Quantity:
20 000
- Current page: 73 of 387
- Download datasheet (5Mb)
Chip Selects and Wait States
PS027001-0707
Memory and I/O Chip Selects
Memory Chip Select Operation
The eZ80F91 generates four chip selects for external devices. Each chip select is pro-
grammed to access either the memory space or the I/O space. The memory chip selects are
individually programmed on a 64 KB boundary. Each I/O chip selects choose a 256-byte
section of I/O space. In addition, each chip select is programmed for up to 7 Wait states.
Each of the chip selects are enabled either for the memory address space or the I/O address
space, but not both. To select the memory address space for a particular chip select,
CSX_IO (CSx_CTL[4]) must be reset to 0. To select the I/O address space for a particular
chip select, CSX_IO must be set to 1. After RESET, the default is for all chip selects to be
configured for the memory address space. For either the memory address space or the I/O
address space, the individual chip selects must be enabled by setting CSX_EN
(CSx_CTL[3]) to 1.
Operation of each of the memory chip select is controlled by three control registers. To
enable a particular memory chip select, the following conditions must be satisfied:
•
•
•
•
•
•
•
If all the preceding conditions are satisfied to generate a memory chip select, then the fol-
lowing results occur:
•
•
•
The chip select is enabled by setting CSx_EN to 1.
The chip select is configured for memory by clearing CSX_IO to 0.
The address is in the associated chip select range:
CSx
On-chip Flash is not configured for the same address space, because on-chip Flash is
prioritized higher than all memory chip selects.
On-chip RAM is not configured for the same address space, because on-chip RAM is
prioritized higher than Flash and all memory chip selects.
No higher priority (lower number) chip select meets the above conditions.
A memory access instruction must be executing.
The appropriate chip select—CS0, CS1, CS2, or CS3 is asserted (driven Low).
MREQ is asserted (driven Low).
Depending on the instruction either RD or WR is asserted (driven Low).
_LBR[7:0]
≤
ADDR[23:16]
≤ CSx
_UBR[7:0].
Chip Selects and Wait States
Product Specification
eZ80F91 ASSP
65
Related parts for ez80f91
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
![ez80f915005modg](/images/no-image3.png)
Part Number:
Description:
Ez80f91 Mini Enet Module
Manufacturer:
ZiLOG Semiconductor
Datasheet:
![EZ800000100STO](/images/manufacturer_photos/0/7/729/zilog_tmb.jpg)
Part Number:
Description:
Development Boards & Kits - Other Processors ZiLOG TCP/IP Software Suite (ZTP Rev 1.4) - Object Code (Free download on www.zilog.com)
Manufacturer:
ZiLOG
![z90231](/images/no-image3.png)
Part Number:
Description:
Z90233, Z90234, And Z90231 Ezvision 200 Television Controller
Manufacturer:
ZiLOG Semiconductor
Datasheet:
![z90212](/images/no-image3.png)
Part Number:
Description:
Digital Television Controllers
Manufacturer:
ZiLOG Semiconductor
Datasheet:
![z90209](/images/no-image3.png)
Part Number:
Description:
Television Controllers
Manufacturer:
ZiLOG Semiconductor
Datasheet:
![z90102](/images/no-image3.png)
Part Number:
Description:
40-pin Low-cost Digital Television Controller
Manufacturer:
ZiLOG Semiconductor
Datasheet:
![z90120](/images/no-image3.png)
Part Number:
Description:
40-pin Low-cost Digital Television Controller
Manufacturer:
ZiLOG Semiconductor
Datasheet:
![z90349](/images/no-image3.png)
Part Number:
Description:
Digital Television Controller In-circuit Emulator Ice Device
Manufacturer:
ZiLOG Semiconductor
Datasheet:
![z90341](/images/no-image3.png)
Part Number:
Description:
Digital Television Controller
Manufacturer:
ZiLOG Semiconductor
Datasheet:
![z90365](/images/no-image3.png)
Part Number:
Description:
Digital Television Controller
Manufacturer:
ZiLOG Semiconductor
Datasheet:
![z16f2811](/images/no-image3.png)
Part Number:
Description:
High Performance Microcontrollers
Manufacturer:
ZiLOG Semiconductor
Datasheet:
![z16c30](/images/no-image3.png)
Part Number:
Description:
Cmos Usc Universal Serial Controller
Manufacturer:
ZiLOG Semiconductor
Datasheet:
![z16c32](/images/no-image3.png)
Part Number:
Description:
Iusc Integrated Universal Serial Controller
Manufacturer:
ZiLOG Semiconductor
Datasheet:
![z16c01](/images/no-image3.png)
Part Number:
Description:
16-bit Processor
Manufacturer:
ZiLOG Semiconductor
Datasheet:
![z16017](/images/no-image3.png)
Part Number:
Description:
Pcmcia Interface Solution
Manufacturer:
ZiLOG Semiconductor
Datasheet: