Z8F16800144ZCOG Zilog, Z8F16800144ZCOG Datasheet - Page 296

• 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

PS025011-1010
Table 159. Write Status Byte
BITS
FIELD
DEFAULT
VALUE
Note:
Byte Write
To write a byte to the NVDS array, the user code must first push the address, then the data
byte onto the stack. The user code issues a
Write routine (
working register R0. The bit fields of this status byte are defined in
user code should pop the address and data bytes off the stack.
The write routine uses 16 bytes of stack space in addition to the two bytes of address and
data pushed by the user code. Sufficient memory must be available for this stack usage.
Because of the flash memory architecture, NVDS writes exhibit a non-uniform execution
time. In general, a write takes 136 s (assuming a 20 MHz system clock). For every 200
writes, however, a maintenance operation is necessary. In this rare occurrence, the write
takes up to 58 ms to complete. Slower system clock speeds result in proportionally higher
execution times.
NVDS byte writes to invalid addresses (those exceeding the NVDS array size) have no
effect. Illegal write operations have a 7 s execution time.
When the NVDS array size is 256 bytes, there is no address exceeding the size, the
bit is of no use.
7
0
Reserved—Must be 0.
FE—Flash Error
If Flash error is detected, this bit is set to 1.
IGADDR—Illegal address
When NVDS byte writes to invalid addresses (those exceeding the NVDS array size)
occur, this bit is set to 1.
WE—Write Error
A failure occurs during writing data into Flash. When writing data into a certain
address, a read back operation is performed. If the read back value is not the same as
the value written, this bit is set to 1.
6
0
0x43FD
Reserved
). At the return from the sub-routine, the write status byte resides in
5
0
P R E L I M I N A R Y
4
0
CALL
3
0
instruction to the address of the Byte
Z8 Encore! XP
FE
2
0
Product Specification
Non-Volatile Data Storage
Table
IGADDR
1
0
®
159. Also, the
F1680 Series
IGADDR
WE
0
0
282