P89LV51RD2BBC NXP Semiconductors, P89LV51RD2BBC Datasheet - Page 41

• Manufacturer Part Number: P89LV51RD2BBC
• Description: MCU 8-Bit 89LV 80C51 CISC 64KB Flash 3.3V 44-Pin TQFP Tray
• Manufacturer: NXP Semiconductors

Specifications of P89LV51RD2BBC

• Package: 44TQFP
• Device Core: 80C51
• Family Name: 89LV
• Maximum Speed: 40 MHz
• Ram Size: 1 KB
• Program Memory Size: 64 KB
• Operating Supply Voltage: 3.3 V
• Data Bus Width: 8 Bit
• Program Memory Type: Flash
• Number Of Programmable I/os: 32
• Interface Type: SPI/UART
• Operating Temperature: 0 to 70 °C
• Number Of Timers: 3

NXP Semiconductors
P89LV51RB2_RC2_RD2_5
Product data sheet
Fig 15. Schemes used by the UART to detect ‘given’ and ‘broadcast’ addresses when multiprocessor
communications is enabled
The following examples help to show the versatility of this scheme.
Example 1, slave 0:
Example 2, slave 1:
In the above example value SADDR is the same and the SADEN data is used to
differentiate between the two slaves. Slave 0 requires a ‘0’ in bit 0 and it ignores bit 1.
Slave 1 requires a ‘0’ in bit 1 and bit 0 is ignored. A unique address for Slave 0 would be
1100 0010 since slave 1 requires a ‘0’ in bit 1. A unique address for slave 1 would be 1100
0001 since a ‘1’ in bit 0 will exclude slave 0. Both slaves can be selected at the same time
by an address which has bit 0 = 0 (for slave 0) and bit 1 = 0 (for slave 1). Thus, both could
be addressed with 1100 0000.
SADDR = 1100 0000
--------------------------------------------------- -
SADDR = 1100 0000
--------------------------------------------------- -
SADEN = 1111 1101
SADEN = 1111 1110
rx_byte(7)
rx_byte(0)
Given = 1100 00X0
Given = 1100 000X
saden(7)
saden(0)
saddr(7)
saddr(0)
saddr(7)
saddr(0)
logic used by UART to detect 'given address' in received data
logic used by UART to detect 'given address' in received data
rx_byte(7)
rx_byte(0)
saden(7)
saden(0)
Rev. 05 — 15 December 2009
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given_address_match
broadcast_address_match
P89LV51RB2/RC2/RD2
8-bit microcontrollers with 80C51 core
002aaa527
© NXP B.V. 2009. All rights reserved.
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