Rainbow Electronics AT90LS4433 - Manual (Page 86)

86
AT90S/LS4433
1042G–AVR–09/02
Programming the Flash
and EEPROM Atmel’s AT90S4433 offers 4K bytes of In-System Reprogrammable Flash Program
memory and 256 bytes of EEPROM Data memory.
The AT90S4433 is shipped with the On-chip Flash Program and EEPROM Data mem-
ory arrays in the erased state (i.e., contents = $FF) and ready to be programmed. This
device supports a High-voltage (12V) Parallel Programming mode and a Low-voltage
Serial Programming mode. The +12V is used for programming enable only, and no cur-
rent of significance is drawn by this pin. The Serial Programming mode provides a
convenient way to download program and data into the AT90S4433 inside the user’s
system.
The Program and Data memory arrays on the AT90S4433 are programmed byte-by-
byte in either Programming mode. For the EEPROM, an auto-erase cycle is provided
within the self-timed write instruction in the Serial Programming mode. During program-
ming, the supply voltage must be in accordance with Table 29.
Parallel Programming This section describes how to Parallel program and verify Flash Program memory,
EEPROM Data memory, Lock bits and Fuse bits in the AT90S4433.
Signal Names In this section, some pins of the AT90S4433 are referenced by signal names describing
their function during Parallel programming. See Figure 62 and Table 30. Pins not
described in Table 30 are referenced by pin name.
The XA1/XA0 pins determine the action executed when the XTAL1 pin is given a posi-
tive pulse. The bit codings are shown in Table 31.
When pulsing WR or OE, the command loaded determines the action executed. The
command is a byte where the different bits are assigned functions as shown in Table 32.
Figure 62. Parallel Programming
Table 29. Supply Voltage during Programming
Part Serial Programming Parallel Programming
AT90LS4433 2.7 - 6.0V 4.5 - 5.5V
AT90S4433 4.0 - 6.0V 4.5 - 5.5V
AT90S4433
VCC
+5V
RESET
GND
XTAL1
PD1
PD2
PD3
PD4
PD5
PD6
+12V
RDY/BSY
OE
BS
XA0
XA1
WR
PC1 - PC0,
PB5 - PB0
DATA