phyCORE-P8xC51Mx2
18
PHYTEC MMesstechnikGmbH 2005 L-602e_3
3.5
J7 SRAM Supply Voltage
The SRAM devices at U5 and U6 can be connected to VCC or VPD
using Jumper J7. As default, the SRAM voltage supply pins are
connected to VCC. Alternatively, the circuit supply pins can be
applied to the battery voltage VPD for purposes of data buffering.
This requires use of standard SRAMs at U5 and U6. Data buffering is
not possible if high-speed SRAMs are installed.
The following configurations are possible:
SRAM Supply Voltage
J7
VCCRAM connected to VCC
1 + 2*
VCCRAM connected to VPD
2 + 3
*= Default setting
Table 7:
J7 SRAM Supply Voltage
3.6
J8, J9 P3.0 and P3.1 as RxD0 and TxD0 Signals
Jumpers J8 and J9 connect the controller RxD0 input port P3.0 and
the TxD0 output port P3.1 to the on-board RS-232 transceiver.
Optionally, P3.0/RxD0 and P3.1/TxD0 can be used as standard I/O at
pins X1D11 and X1E11 of the phyCORE-connector. This requires
opening Jumpers J8 and J9.
The following configurations are possible:
P3.0 and P3.1 - Serial Interface
J8, J9
P3.0 and P3.1 as RS-232
closed*
P3.0 and P3.1 as port pins
open
*= Default setting
Table 8:
J8, J9 Port P3.0 and P3.1 / 1
st
Serial Interface Configuration
