Rainbow Electronics ATmega64L - Manual (Page 256)

256
ATmega16(L)
2466B–09/01
The XA1/XA0 pins determine the action executed when the XTAL1 pin is given a posi-
tive pulse. The bit coding is shown in Table 109.
When pulsing WR or OE, the command loaded determines the action executed. The dif-
ferent Commands are shown in Table 110.
Figure 128. Parallel Programming
Table 107. Pin Name Mapping
Signal Name in
Programming Mode
Pin Name I/O Function
RDY/BSY PD1 O
0: Device is busy programming, 1: Device is ready
for new command
OE PD2 I Output Enable (Active low)
WR PD3 I Write Pulse (Active low)
BS1 PD4 I
Byte Select 1 ("0" selects low byte, "1" selects high
byte)
XA0 PD5 I XTAL Action Bit 0
XA1 PD6 I XTAL Action Bit 1
PAGEL PD7 I Program Memory and EEPROM data Page Load
BS2 PA0 I
Byte Select 2 ("0" selects low byte, "1" selects 2"nd
high byte)
DATA PB7-0 I/O Bidirectional Data bus (Output when OE is low)
VCC
+5V
GND
XTAL1
PD1
PD2
PD3
PD4
PD5
PD6
PB7 - PB0 DATA
RESET
PD7
+12 V
BS1
XA0
XA1
OE
RDY/BSY
PAGEL
PA0
WR
BS2