PEB20534H-10 SIEMENS [Siemens Semiconductor Group], PEB20534H-10 Datasheet - Page 196

• Manufacturer Part Number: PEB20534H-10
• Description: DMA Supported Serial Communication Controller with 4 Channels DSCC4
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

Semiconductor Group
Figure 72 shows the connection between two SCC devices as DTEs. The RTS of DTE-
A (SCC) feeds the CTS input of the second DTE-B (another SCC). For example while
DTE-A is receiving data and its receive FIFO threshold is reached, the RTS signal goes
in-active ’HIGH’ forcing the CTS of DTE-B to become in-active indicating that
transmission has to stop after finishing the current character. Both DTE devices should
also be using the CTS signal to flow control their transmitters. When the shadow receive
FIFO in DTE-A is cleared its RTS goes active ‘LOW’ and this signals the far end DTE-B
to resume transmission. Data flow control from DTE,-B to DTE-A works in the same way.
Figure 72
DTE A
Out-of-Band DTE-DTE Bi-directional Flow Control
DSCC4
TxD
RTS
RxD
CTS
RS232c Signals
(drivers not shown)
196
Detailed Protocol Description
DTE
CTS
TxD
RxD
RTS
DSCC4
B
ITS08517
Data Sheet 09.98
PEB 20534