Intel 8XC196K Series User Manual page 404

Special
Port Pin Function
Signal
P4.7:0, PBUS
P3.7:0
P1.2:1 PBUS
P4.7:5,
P3.7:0
— EA#
— V
PP
PROGRAMMING THE NONVOLATILE MEMORY
Table 16-6. Pin Descriptions (Continued)
Program-
Type ming
Mode
I/O Slave Address/Command/Data Bus
During slave programming, ports 3 and 4 serve as a
bidirectional port with open-drain outputs to pass
commands, addresses, and data to or from the device.
Slave programming requires external pull-up resistors.
I/O Auto Address/Command/Data Bus
ROM-
During auto programming and ROM-dump, ports 3 and 4
dump
serve as a regular system bus to access external
memory.
P4.6 and P4.7 are left unconnected; P1.2 and P1.1 serve
as the upper address lines.
I All External Access
Controls program mode entry. If EA# is at V
the rising edge of RESET#, the device enters
programming mode.
EA# is sampled and latched only on the rising edge of
RESET#. Changing the level of EA# after reset has no
effect.
I All Programming Voltage
During programming, the V
(V
PP
fication can damage the device.
Description
pin is typically at +12.5V
PP
voltage). Exceeding the maximum V
voltage on
PP
voltage speci-
PP
16-13