MC9S12HZ256 Datasheet, PDF (103/692 Pages) Freescale Semiconductor, Inc – HCS12 Microcontrollers

Chapter 3 2 Kbyte EEPROM Module (EETS2KV1)
7
6
5
4
3
2
1
0
R
CCIF
0
BLANK
0
0
CBEIF
PVIOL
ACCERR
W
Reset
1
1
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 3-9. EEPROM Status Register (ESTAT - Normal Mode)
R
W
Reset
7
CBEIF
1
6
5
4
3
CCIF
0
PVIOL
ACCERR
2
BLANK
1
FAIL
1
0
0
0
0
0
= Unimplemented or Reserved
Figure 3-10. EEPROM Status Register (ESTAT - Special Mode)
0
DONE
1
CBEIF, PVIOL, and ACCERR bits are readable and writable, CCIF and BLANK bits are readable but not
writable, remaining bits read 0 and are not writable in normal mode. FAIL is readable and writable in
special mode. FAIL must be clear when starting a command write sequence. DONE is readable but not
writable in special mode.
Table 3-7. ESTAT Field Descriptions
Field
7
CBEIF
6
CCIF
5
PVIOL
Description
Command Buffer Empty Interrupt Flag — The CBEIF flag indicates that the address, data, and command
buffers are empty so that a new command sequence can be started. The CBEIF flag is cleared by writing a 1 to
CBEIF. Writing a 0 to the CBEIF flag has no effect on CBEIF. Writing a 0 to CBEIF after writing an aligned word
to the EEPROM address space but before CBEIF is cleared will abort a command sequence and cause the
ACCERR flag in the ESTAT register to be set. Writing a 0 to CBEIF outside of a command sequence will not set
the ACCERR flag. The CBEIF flag is used together with the CBEIE bit in the ECNFG register to generate an
interrupt request.
0 Buffers are full
1 Buffers are ready to accept a new command
Command Complete Interrupt Flag — The CCIF flag indicates that there are no more commands pending. The
CCIF flag is cleared when CBEIF is cleared and sets automatically upon completion of all active and pending
commands. The CCIF flag does not set when an active command completes and a pending command is fetched
from the command buffer. Writing to the CCIF flag has no effect. The CCIF flag is used together with the CCIE
bit in the ECNFG register to generate an interrupt request.
0 Command in progress
1 All commands are completed
Protection Violation — The PVIOL flag indicates an attempt was made to program or erase an address in a
protected EEPROM memory area (Section 3.4.1.4, “Illegal EEPROM Operations”). The PVIOL flag is cleared by
writing a 1 to PVIOL. Writing a 0 to the PVIOL flag has no effect on PVIOL. While PVIOL is set, it is not possible
to launch another command in the EEPROM.
0 No failure
1 A protection violation has occurred
MC9S12HZ256 Data Sheet, Rev. 2.04
Freescale Semiconductor
103