R8CSLASH15 datasheet(257/277 Pages) RENESAS

257 / 277 page

R8C/14 Group, R8C/15 Group

20. Precautions

Rev.2.10

Jan 19, 2006

Page 245 of 253

REJ09B0164-0210

20.8

Flash Memory Version

20.8.1

CPU Rewrite Mode

20.8.1.1

Operating Speed

Before entering CPU rewrite mode (EW0 mode), select 5MHz or below for the CPU clock using the

CM06 bit in the CM0 register and the CM16 to CM17 bits in the CM1 register. This usage note is not

needed for EW1 mode.

20.8.1.2

Instructions Inhibited Against Use

The following instructions cannot be used in EW0 mode because the flash memory internal data is

referenced: UND, INTO, and BRK instructions.

20.8.1.3

Interrupts

Table 20.1 lists the Interrupt in EW0 Mode and Table 20.2 lists the Interrupt in EW1 Mode.

NOTES:

1. Do not use the address match interrupt while the command is executed because the vector of the

address match interrupt is allocated on ROM.

2. Do not use the non-maskable interrupt while Block 0 is automatically erased because the fixed

vector is allocated Block 0.

Table 20.1

Interrupt in EW0 Mode

Mode

Status

When maskable

interrupt request is

acknowledged

When watchdog timer, oscillation stop detection and

voltage monitor 2 interrupt request are acknowledged

EW0 During automatic

erasing

Any interrupt can be

used by allocating a

vector to RAM

Once an interrupt request is acknowledged, the auto-

programming or auto-erasing is forcibly stopped

immediately and resets the flash memory. An interrupt

process starts after the fixed period and the flash

memory restarts. Since the block during the auto-erasing

or the address during the auto-programming is forcibly

stopped, the normal value may not be read. Execute the

auto-erasing again and ensure the auto-erasing is

completed normally.

Since the watchdog timer does not stop during the

command operation, the interrupt request may be

generated. Reset the watchdog timer regularly.

Automatic writing

R8C/15 Datasheet(PDF) 257 Page - Renesas Technology Corp

R8C/15 Datasheet(HTML) 257 Page - Renesas Technology Corp

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL