Z8F16800144ZCOG Zilog, Z8F16800144ZCOG Datasheet - Page 295

• Manufacturer Part Number: Z8F16800144ZCOG
• Description: KIT DEV FOR Z8F642 MCU 44 PIN
• Manufacturer: Zilog
• Series: Z8 Encore!®r
• Type: MCUr

Specifications of Z8F16800144ZCOG

• Contents: Hardware, Software and Documentation
• For Use With/related Products: Z8F642
• For Use With: 269-4661 - KIT ACC ETHERNET SMART CABLE
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 269-4678

Non-Volatile Data Storage
Overview
Operation
NVDS Code Interface
PS025011-1010
Note:
The Z8 Encore! XP F1680 Series devices contain a Non-Volatile Data Storage (NVDS)
element of up to 256 bytes. This memory can perform over 100,000 write cycles.
The NVDS is implemented by special purpose Zilog
memory not accessible to you. These special-purpose routines use the Flash memory to
store the data. The routines incorporate a dynamic addressing scheme to maximize the
Write/Erase endurance of the Flash.
Different members of the Z8 Encore! XP F1680 Series feature multiple NVDS array sizes.
For more details, see
Two routines are required to access the NVDS: a write routine and a read routine. Both of
these routines are accessed with a CALL instruction to a pre-defined address outside the
program memory accessible to you. Both the NVDS address and data are single-byte val-
ues. In order NOT to disturb the user code, these routines save the working register set
before using it, so 16 bytes of stack space is needed to preserve the site. After finishing the
call to these routines, the working register set of the user code is recovered.
During both read and write accesses to the NVDS, interrupt service is NOT disabled. Any
interrupts that occur during the NVDS execution must not disturb the working register and
existing stack contents; or else the array becomes corrupted. Disabling interrupts before
executing NVDS operations is recommended.
Use of the NVDS requires 16 bytes of available stack space. The contents of the working
register set are saved before calling NVDS read or write routines.
For correct NVDS operation, the Flash Frequency Registers must be programmed based
on the system clock frequency. For more details, see
Frequency Registers
on page 258.
Table 1
P R E L I M I N A R Y
on page 2.
®
Flash Operation Timing Using Flash
software stored in areas of Program
Z8 Encore! XP
Product Specification
Non-Volatile Data Storage
®
F1680 Series
281