CHAPTER 15 FLASH MEMORY (
µ
PD70F3114)
625
User’s Manual U15195EJ5V0UD
Setting data to the flash programming mode control register (FLPMC) is performed in the following sequence.
<1> Disable interrupts (set the NP bit and ID bit of the PSW to 1).
<2> Prepare the data to be set in the specific register in a general-purpose register.
<3> Write data to the peripheral command register (PHCMD).
<4> Set the flash programming mode control register (FLPMC) by executing the following instructions.
•
Store instruction (ST/SST instructions)
•
Bit manipulation instruction (SET1/CLR1/NOT1 instructions)
<5> Insert NOP instructions (5 instructions (<5> to <9>)).
<10> Cancel the interrupt disabled state (reset the NP bit of the PSW to 0).
[Description example]
<1>
LDSR rX, 5
<2>
MOV 0x02, r10
<3>
ST.B r10, PHCMD[r0]
<4>
ST.B r10, FLPMC[r0]
<5>
NOP
<6>
NOP
<7>
NOP
<8>
NOP
<9>
NOP
<10>
LDSR rY, 5
Remark
rX: Value written to the PSW
rY: Value returned to the PSW
No special sequence is required for reading a specific register.
Cautions 1. If an interrupt is acknowledged between when PHCMD is issued (<3>) and writing to a
specific register (<4>) immediately after issuing PHCMD, writing to the specific register may
not be performed and a protection error may occur (the PRERR bit of the PHS register = 1).
Therefore, set the NP bit of the PSW to 1 (<1>) to disable interrupt acknowledgment.
Similarly, disable acknowledgment of interrupts when a bit manipulation instruction is used
to set a specific register.
2. Use the same general-purpose register used to set a specific register (<3>) for writing to the
PHCMD register (<4>) even though the data written to the PHCMD register is dummy data.
This is the same as when a general-purpose register is used for addressing.
3. Before executing this processing, complete all DMA transfer operations.
