M-V850E-IA4 Renesas Electronics America, M-V850E-IA4 Datasheet - Page 79

• Manufacturer Part Number: M-V850E-IA4
• Description: KIT EVAL V850E IA4 UPD70F3186
• Manufacturer: Renesas Electronics America

Specifications of M-V850E-IA4

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

(1) Setting data to special registers
Cautions 1. When a store instruction is executed to store data in the command register, interrupts are
Set data to the special registers in the following sequence.
<1> Prepare data to be set to the special register in a general-purpose register.
<2> Write the data prepared in <1> to the command register.
<3> Write the setting data to the special register (by using the following instructions).
(<4> to <8> Insert NOP instructions (5 instructions).)
There is no special sequence to read a special register.
Note Five NOP instructions or more must be inserted immediately after setting the IDLE mode or STOP
[Example] With PSC register (setting standby mode)
<1>MOV 0x02, r10
<2>ST.B r10, PRCMD[r0] ; Write PRCMD register.
<3>ST.B r10, PSC[r0]
<4>NOP
<5>NOP
<6>NOP
<7>NOP
<8>NOP
(next instruction)
• Store instruction (ST/SST instruction)
• Bit manipulation instruction (SET1/CLR1/NOT1 instruction)
ST.B r11, PSMR[r0]
mode (by setting the PSC.STB bit to 1).
Note
Note
Note
Note
Note
2. Although dummy data is written to the command register, use the same general-purpose
3. Before executing this processing, terminate all DMA transfer operations.
not acknowledged. This is because it is assumed that steps <2> and <3> above are
performed by successive store instructions. If another instruction is placed between <2>
and <3>, and if an interrupt is acknowledged by that instruction, the above sequence may
not be established, causing malfunction.
register used to set the special register (<3> in Example) by using the store instruction to
write data to the command register (<2> in Example). The same applies when a general-
purpose register is used for addressing.
An example of setting the special register (<3> in Example) by using the bit manipulation
instruction is shown below.
CLR1 4, RESF[r0]
; Set PSMR register (setting IDLE and STOP modes).
; Set PSC register.
; Dummy instruction
; Dummy instruction
; Dummy instruction
; Dummy instruction
; Dummy instruction
CHAPTER 3 CPU FUNCTION
User’s Manual U16543EJ4V0UD
Note
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