Serial Interface with Time Slot Assigner
MOTOROLA
MC68360 USER’S MANUAL
7-87
7.8.5.4 SI COMMAND REGISTER (SICMR).
The 8-bit SICMR allows the user to dynami-
cally program the SI RAM. For more information about dynamic programming, refer to
7.8.4.7 SI RAM Dynamic Changes
The contents of this register are valid only in the RAM division mode (RDM1–RDM0 bits in
SIGMR equal 01 or 11). This register is cleared at reset.
CSRRx—Change Shadow RAM for TDM A or B Receiver
When set, this bit will cause the SI receiver to replace the current route with the shadow
RAM. The bit is set by the user and cleared by the SI.
0 = The receiver shadow RAM is not valid. The user can write into the shadow RAM to
program a new routing.
1 = The receiver shadow RAM is valid. The SI will exchange between the RAMs and
take the new receive routing from the receiver shadow RAM. This bit is cleared as
soon as the switch has completed.
CSRTx—Change Shadow RAM for TDM A or B Transmitter
When set, this bit will cause the SI transmitter to replace the current route with the shadow
RAM. The bit is set by the user and cleared by the SI.
0 = The transmitter shadow RAM is not valid. The user can write into the shadow RAM
to program a new routing.
1 = The transmitter shadow RAM is valid. The SI will exchange between the RAMs and
take the new transmitter routing from the receiver shadow RAM. This bit is cleared
as soon as the switch has completed.
Bits 3–0—Reserved
These bits should be set to zero by the user.
7.8.5.5 SI STATUS REGISTER (SISTR).
The 8-bit SISTR indicates to the user which part
of the SI RAM is the current-route RAM. The value of this register is valid only when the cor-
responding bit in the SIGMR is clear. This register is cleared at reset.
CRORa—Current Route of TDMa Receiver
0 = The current-route receiver RAM is in address:
0–63 when the SI supports one TDM (RDM = 01)
0–31 when the SI supports two TDMs (RDM = 11)
1 = The current route receiver RAM is in address:
64–127 when the SI supports one TDM (RDM = 01)
32–63 when the SI supports two TDMs (RDM = 11)
7
6
5
4
3
2
1
0
CSRRa
CSRTa
CSRRb
CSRTb
—
7
6
5
4
3
2
1
0
CRORa
CROTa
CRORb
CROTb
—