Reference Manual

PMAC-PCI Hardware Reference
PMAC-PCI E-Point Jumper Descriptions 19
E44 - E47: Serial Port Baud Rate
Jumpers E44 - E47 control what baud rate to use for serial communications. Any character received over
the bus causes PMAC to use the bus for its standard communications. The serial port is disabled if E44-
E47 are all on. The baud rate setting of an 80 MHz CPU section ordered with Opt 5C is performed by
software; refer to the dedicated section on the Software Configuration chapter of this manual.
Baud Rate Control E Points Baud Rate
Default and
Physical Layout
E44 E45 E46 E47 Option
4A
Standard,
Option
5A
Option 5,
Option
5B
E44 E45 E46 E47
Loc. B5 B5 C5 C5
ON ON ON ON Disabled Disabled Disabled
OFF ON ON ON 300 600 900
ON OFF ON ON 400* 800* 1200
Picture is for a PMAC
with a Standard or
Option 5A CPU
OFF OFF ON ON 600 1200 1800
ON ON OFF ON 800* 1600* 2400
OFF ON OFF ON 1200 2400 3600
ON OFF OFF ON 1600* 3200* 4800
OFF OFF OFF ON 2400 4800 7200
ON ON ON OFF 3200* 6400* 9600 Options 5, 5B
OFF ON ON OFF 4800 9600 14400 Std., Option 5A
ON OFF ON OFF 6400* 12800* 19200
OFF OFF ON OFF 9600 19200 28800 Option 4A
ON ON OFF OFF 12800* 25600* 38400
OFF ON OFF OFF 19200 38400 57600
ON OFF OFF OFF 25600* 51200* 76800
OFF OFF OFF OFF 38400 76800 115200
Note: These jumpers are only used to set the baud rate at power-on/reset. Currently, Flex CPU’s
communication baud rate is determined at power-up/reset by variable I54.
* Non-standard baud rates.
E48: CPU Clock Frequency Control (Option CPU Section)
E48 controls the CPU clock frequency only on PMAC with an option CPU section using flash memory
backup (no battery). This CPU section is used on PMACs ordered with Opt 4A, 5A, or 5B. The 80 MHz
setting of a CPU section ordered with Opt 5C is performed by software; refer to the dedicated section on
the Software Configuration chapter of this manual.
E Point and
Physical Layout
Location Description Default
E48
C5 Jump pins 1 and 2 to multiply crystal frequency
by 3 inside CPU for 60 MHz operation.
Remove jumper to multiply crystal frequency
by 2 inside CPU for 40 MHz operation.
Jumper installed
(Option 5, 5B)
Jumper not
installed (Standard,
Option 4A, 5A)
Note: It may be possible to operate a board with 40 MHz components (Option 5A) at 60 MHz under
some conditions by changing the setting of jumper E48. However, this operates the components outside
of their specified operating range, and proper execution of PMAC under these conditions is not
guaranteed. PMAC software failure is possible, even probable, under these conditions, and this can lead
to very dangerous machine failure. Operation in this mode is done completely at the user’s own risk.
Delta Tau can accept no responsibility for the operation of PMAC or the machine under these conditions.