Datasheet

289
4317K–AVR–03/2013
AT90PWM2/3/2B/3B
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 (See Figure 25-3 for signal waveforms).
I. Repeat B through H until the entire Flash is programmed or until all data has been
programmed.
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.
3. Give XTAL1 a positive pulse. This loads the command, and the internal write signals are
reset.
Figure 25-2. Addressing the Flash Which is Organized in Pages
(1)
Note: 1. PCPAGE and PCWORD are listed in Table 25-11 on page 286.
Figure 25-3. Programming the Flash Waveforms
(1)
Note: 1. “XX” is don’t care. The letters refer to the programming description above.
PROGRAM MEMORY
WORD ADDRESS
WITHIN A PAGE
PAGE ADDRESS
WITHIN THE FLASH
INSTRUCTION WORD
PAGE
PCWORD[PAGEMSB:0]:
00
01
02
PAGEEND
PAGE
PCWORDPCPAGE
PCMSB
PAGEMSB
PROGRAM
COUNTER
RDY/BSY
WR
OE
RESET +12V
PAGEL
BS2
0x10 ADDR. LOW
ADDR. HIGH
DATA
DATA L OW DATA H IG H
ADDR. LOW DATA LOW DATA HIGH
XA1
XA0
BS1
XTAL1
XX XX
XX
ABCDEB CDEGH
F