Zilog Z80230 - Manual (Page 194)

SCC/ESCC
User Manual
UM010903-0515 Register Descriptions
187
Read Register 13
RR13 returns the value stored in WR13, the upper byte of the time constant for the BRG. Figure
displays the bit positions for RR13.
Read Register 13
Read Register 14 (ESCC and 85C30 Only)
On the ESCC, Read Register 14 reflects the contents of Write Register 7 Prime provided the
Extended Read option has been enabled. Otherwise, this register returns an image of RR10.
On the NMOS/CMOS version, a read to this location returns an image of RR10.
Read Register 15
RR15 reflects the value stored in WR15, the External/Status IE bits. The two unused bits are
always returned as Os. Figure displays the bit positions for RR15.
Read Register 15
D7 D6 D5 D4 D3 D2 D1 D0
Read Register 13
TC8
TC9
TC10
TC11
TC12
TC13
TC14
TC15
Upper Byte
of Time Constant
D7 D6 D5 D4 D3 D2 D1 D0
Read Register 15
0
Zero Count IE
0
DCD IE
Sync/Hunt IE
CTS IE
Tx Underrun/EOM IE
Break/Abort IE