MC68HC908GR4MP datasheet(110/286 Pages) FREESCALE

110 / 286 page

Flash Memory

MC68HC908GR8 • MC68HC908GR4 Data Sheet, Rev. 7

110

Freescale Semiconductor

11.3 FLASH Control Register

The FLASH control register (FLCR) controls FLASH program and erase operations.

HVEN — High-Voltage Enable Bit

This read/write bit enables the charge pump to drive high voltages for program and erase operations

in the array. HVEN can only be set if either PGM = 1 or ERASE = 1 and the proper sequence for

program or erase is followed.

1 = High voltage enabled to array and charge pump on

0 = High voltage disabled to array and charge pump off

MASS — Mass Erase Control Bit

Setting this read/write bit configures the 8K byte FLASH array for mass erase operation.

1 = MASS erase operation selected

0 = MASS erase operation unselected

ERASE — Erase Control Bit

This read/write bit configures the memory for erase operation. ERASE is interlocked with the PGM bit

such that both bits cannot be equal to 1 or set to 1 at the same time.

1 = Erase operation selected

0 = Erase operation unselected

PGM — Program Control Bit

This read/write bit configures the memory for program operation. PGM is interlocked with the ERASE

bit such that both bits cannot be equal to 1 or set to 1 at the same time.

1 = Program operation selected

0 = Program operation unselected

11.4 FLASH Page Erase Operation

Use this step-by-step procedure to erase a page (64 bytes) of FLASH memory. A page consists of 64

consecutive bytes starting from addresses $XX00, $XX40, $XX80, or $XXC0. The user interrupt vector

area also forms a page. Any FLASH memory page can be erased alone.

Set the ERASE bit, and clear the MASS bit in the FLASH control register.

Read the FLASH block protect register.

Write any data to any FLASH address within the page address range desired.

Wait for a time, tnvs (min. 10μs)

Set the HVEN bit.

Wait for a time, tErase (min. 1ms)

Clear the ERASE bit.

Address:

$FE08

Bit 7

654321

Bit 0

Read:

0000

HVEN

MASS

ERASE

PGM

Write:

Reset:

00000000

= Unimplemented

Figure 11-1. FLASH Control Register (FLCR)

MC68HC908GR4MP Datasheet(PDF) 110 Page - Freescale Semiconductor, Inc

MC68HC908GR4MP Datasheet(HTML) 110 Page - Freescale Semiconductor, Inc

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