Sharp UP-3301 Service Manual page 54

2) DATA COMMUNICATION
Data is transmitted from the host CPU to the TCP/IP board or vice versa
through the dual-port SRAM. If data is written into the same address of
the dual-port SRAM from both sides or written into and read from the
same address from both sides, data is not assured. The following pro-
cedure should be observed.
The format of data to be handled should meet the software specifica-
tions.
Write
Preceding data read
N
end interrupt?
Y
Write data
Generation of write
end interrupt
• Interrupt signals from the host to board : Write/INTHW (Host Write),
Read/INTHR (Host Read)
/INTHW (Host Write) is generated by writing into the address H'7***
of the dual-port SRAM and cancelled by outputting the /HWACK sig-
nal by 100ns LOW pulse.
/INTHR (Host Read) is generated by reading the address H'B*** of
the dual-port SRAM and cancelled by outputting the /HRACK signal
by 100ns LOW pulse.
• Interrupt signals from the board to host : Write /INTSW (Slave Write),
Read /INTSR (Slave Read)
/INTSW (Slave Write) is generated by outputting the /SWRQ signal
by 100ns LOW pulse and cancelled by writing data into the address
H'B*** of the dual-port SRAM from the host side.
/INTSR (Slave Read) is generated by outputting the /SRRQ signal by
100ns low pulse and cancelled by reading data from the address
H'7*** of the dual-port SRAM.
7. LAN CONTROL
This board fixes RTL8019AS to the 8-bit mode on hardware.
Read
Data write end
N
interrupt?
The initial values of the items in the table are set as shown below by
hardware.
Y
Read data
Generation of read
end interrupt
Any data loading EEPROM is not used. MAC address is written by the
CPU reading data on the flash memory and writing the register to the
LAN controller.
8. PORT SETTING
1 The common pins of the CPU are set as shown below.
UP-3301US CIRCUIT DESCRIPTION
– 52 –
CPU
/CS3
A19-A0
D7-D0
/RD
/WRL
/IRQ2
/WAIT
Item
I/O Base Address 300H
Network Media Type TP/CX automatic
detection
BROM Size & Memory Disable
Base Address
IRQ Select INT0
Pin Selection
I/O
No signal
2 I PE15 /WP(FLASH write STATUS)
24 I /IRQ0 Host write end interrupt (4 Edge detection)
25 I /IRQ1 Host read end interrupt (4 Edge detection)
26 I /IRQ2 Interrupt from LANC (4 Edge detection)
28 I /IRQ3 Reserve (4 Edge detection)
29 O A18 Address Bus
30 O A19 Address Bus
31 I /WAIT wait from LANC
44 O /CS3 Chip Select for LAN (Usual access space)
45 O /CS2 Chip Select for dual-port SRAM
106 O PE8 /SRRQ (Board side read end request)
107 O PE9 /SWRQ (Board side write end request)
108 O PE10 /HRACK
(host side read end interrupt cancel)
110 O PE11 /HWACK
(host side write end interrupt cancel)
112 O PE13 /RSTDRViActive Lowj
RTL8019AS
SLOT16 GND
AEN
SA19-SA0
SD7-SD0
IORB
IOWB
INT0
IOCHRDY
Setting Remarks
IOS3~0=0,0,0,0
PL1~0=0,0
BS4~0=0,0,0,0,0
IRQS2~0=0,0,0
Remarks