Datasheet

ManualsBrandsMICROCHIP TECHNOLOGY ManualsMicrocontrollers, Microprocessors & QuartzesEmbedded microcontroller TQFP 32 (7x7) 8-Bit 20 MHz I/O number 23

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2. Set BS1 to “0”. This selects low address.

3. Set DATA = Address low byte (0x00 - 0xFF).

4. Give XTAL1 a positive pulse. This loads the address low byte.

Step C. Load Data Low Byte

1. Set XA1, XA0 to “01”. This enables data loading.

2. Set DATA = Data low byte (0x00 - 0xFF).

3. Give XTAL1 a positive pulse. This loads the data byte.

Step D. Load Data High Byte

1. Set BS1 to “1”. This selects high data byte.

2. Set XA1, XA0 to “01”. This enables data loading.

3. Set DATA = Data high byte (0x00 - 0xFF).

4. Give XTAL1 a positive pulse. This loads the data byte.

Step E. Latch Data

1. Set BS1 to “1”. This selects high data byte.

2. Give PAGEL a positive pulse. This latches the data bytes. (Refer to figure Programming the Flash

Waveforms, in this section, for signal waveforms.)

Step F. Repeat B Through E Until the Entire Buffer is Filled or Until All Data Within the Page is

Loaded

While the lower bits in the address are mapped to words within the page, the higher bits address the

pages within the FLASH. This is illustrated in the following figure, Addressing the Flash Which is

Organized in Pages, in this section. Note that if less than eight bits are required to address words in the

page (page size < 256), the most significant bit(s) in the address low byte are used to address the page

when performing a page write.

Step G. Load Address High Byte

1. Set XA1, XA0 to “00”. This enables address loading.

2. Set BS1 to “1”. This selects high address.

3. Set DATA = Address high byte (0x00 - 0xFF).

4. Give XTAL1 a positive pulse. This loads the address high byte.

Step H. Program Page

1. Give WR a negative pulse. This starts programming of the entire page of data. RDY/BSY goes low.

2. Wait until RDY/BSY goes high. (Refer to the figure, Programming the Flash Waveforms, in this

section for signal waveforms.)

Step I. Repeat B Through H Until the Entire Flash is Programmed or Until All Data Has Been

Programmed

Step J. End Page Programming

1. 1. Set XA1, XA0 to “10”. This enables command loading.

2. Set DATA to “0000 0000”. This is the command for no operation.

ATmega48PA/88PA/168PA

Memory Programming (MEMPROG)

Datasheet Complete

DS40002011A-page 373