IBM PD78P081(A2) Network Card User Manual


 
167
CHAPTER 11 SERIAL INTERFACE CHANNEL 2
When the internal clock is used as the serial clock in the 3-wire serial I/O mode, set BRGC as described below.
BRGC Setting is not required if an external serial clock is used.
(i) When the baud rate generator is not used:
Select a serial clock frequency with TPS0-TPS3. Be sure then to set MDL0 to MDL3 to 1,1,1,1.
The serial clock frequency becomes the same as the source clock frequency for the 5-bit counter.
(ii) When the baud rate generator is used:
Select a serial clock frequency with TPS0-TPS3. Be sure then to set MDL0 to MDL3 to 1,1,1,1.
The serial clock frequency is calculated by the following formula:
Serial clock frequency= [H
z]
Remarks 1. f
X : Main system clock oscillation frequency
2. f
XX : Main system clock frequency (fX or fX/2)
3. n : Value set in TPS0 to TPS3 (1 n 11)
4. k : Value set in MDL0 to MDL3 (0 k 14)
f
XX
2
n
x (k + 16)