Ssio Transmit Holding Buffer (Ssiotbuf) - Intel 386 User Manual

Intel386™ EX EMBEDDED MICROPROCESSOR USER'S MANUAL

13.3.8 SSIO Transmit Holding Buffer (SSIOTBUF)

Write the data words to be transmitted to SSIOTBUF. Use the interrupt controller, DMA unit or
polling (read SSIOCON1) to determine when to write to the transmit buffer.
Transmit Holding Buffer
SSIOTBUF
(read/write)
15
TB15 TB14
7
TB7 TB6
Bit Bit
Number Mnemonic
15–0 TB15:0
Figure 13-22. SSIO Transmit Holding Buffer (SSIOTBUF)
13-24
TB13 TB12
TB5 TB4
Transmit Buffer Bits:
These bits make up the next data word to be transmitted. The control
logic loads this word into the transmit shift register. The transmit shift
register shifts the bits out on the falling edge of the tranmitter clock pin.
The word is transmitted out starting with the most-significant bit (TB15).
Expanded Addr: F480H
ISA Addr: —
Reset State: 0000H
TB11 TB10
TB3 TB2
Function
8
TB9 TB8
0
TB1 TB0