AT90LS2323-4SC datasheet(39/64 Pages) ATMEL

39 / 64 page

AT90S/LS2323/2343

1004D–09/01

High-voltage Serial

Programming Algorithm

To program and verify the AT90S/LS2323 and AT90S/LS234 in the high-voltage Serial

Programming mode, the following sequence is recommended (see instruction formats in

Table 16):

Power-up sequence: Apply 4.5 - 5.5V between V

CC and GND. Set RESET and

PB0 to “0” and wait at least 100 ns. Then, if the RCEN Fuse is not programmed,

toggle XTAL1/PB3 at least four times with minimum 100 ns pulse width. Set PB3

to “0”. Wait at least 100 ns. Or, if the RCEN Fuse is programmed, set PB3 to “0”.

Wait for least 4 µs. In both cases, apply 12V to RESET and wait at least 100 ns

before changing PB0. Wait 8 µs before giving any instructions.

The Flash array is programmed one byte at a time by supplying first the address,

then the low and high data bytes. The write instruction is self-timed; wait until the

PB2 (RDY/BSY) pin goes high.

The EEPROM array is programmed one byte at a time by supplying first the

address, then the data byte. The write instruction is self-timed; wait until the PB2

(RDY/BSY) pin goes high.

Any memory location can be verified by using the Read instruction, which returns

the contents at the selected address at serial output PB2.

Power-off sequence:Set PB3 to “0”.

Set RESET to “0”.

Turn VCC power off.

When writing or reading serial data to the device, data is clocked on the rising edge of

the serial clock. See Figure 33, Figure 34 and Table 17 for details.

Figure 33. High-voltage Serial Programming Waveforms

MSB

LSB

SERIAL DATA INPUT

PB0

SERIAL INSTR. INPUT

PB1

SERIAL DATA OUTPUT

PB2

SERIAL CLOCK INPUT

XTAL1/PB3

AT90LS2323-4SC датащи(PDF) 39 Page - ATMEL Corporation