SC68C752BIB48 PHILIPS [NXP Semiconductors], SC68C752BIB48 Datasheet - Page 16

• Manufacturer Part Number: SC68C752BIB48
• Description: 5 V, 3.3 V and 2.5 V dual UART, 5 Mbit/s (max.), with 64-byte FIFOs and Motorola uP interface
• Manufacturer: PHILIPS [NXP Semiconductors]

Philips Semiconductors
SC68C752B_3
Product data sheet
6.6.1.1 Transmitter
6.6.1.2 Receiver
6.6.1 Single DMA transfers (DMA mode 0/FIFO disable)
6.6 DMA operation
There are two modes of DMA operation, DMA mode 0 or DMA mode 1, selected by
FCR[3].
In DMA mode 0 or FIFO disable (FCR[0] = 0) DMA occurs in single character transfers. In
DMA mode 1, multi-character (or block) DMA transfers are managed to relieve the
processor for longer periods of time.
Figure 10
When empty, the TXRDY signal becomes active. TXRDY will go inactive after one
character has been loaded into it.
RXRDY is active when there is at least one character in the FIFO. It becomes inactive
when the receiver is empty.
Fig 10. TXRDY and RXRDY in DMA mode 0/FIFO disable
wrptr
wrptr
shows TXRDY and RXRDY in DMA mode 0/FIFO disable.
FIFO EMPTY
5 V, 3.3 V and 2.5 V dual UART, 5 Mbit/s (max.), with 64-byte FIFOs
TX
Rev. 03 — 29 November 2005
TXRDY
TXRDY
location filled
at least one
rdptr
rdptr
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
FIFO EMPTY
RX
SC68C752B
RXRDY
location filled
RXRDY
at least one
002aaa232
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