Hitachi NJI-350B manual Port 2 specifications, Setting port, Bit WRF03D Initial value, 11-3

Chapter 11 Communication Specifications

11.3 Port 2

The specifications of port 2 are listed in Table 11.4. 1:n station communication by the high protocol is possible with port 2. By creating and including a control procedure based on the high protocol on the personal computer which will become the host, it becomes possible to control a maximum of 32 stations from one host. The systems can thus be configured in several ways.

Table 11.4 Port 2 specifications

Item	Specification
	Dedicated (programming) port	General purpose port
Communication speed	4800, 9600, 19.2 k, 38.4 k bps	300, 600, 1200, 2400, 4800, 9600, 19.2 k,
		38.4 k, 57.6 k bps
Communication system	Half duplex
Synchronization	Asynchronous
Startup system	One-sided startup using the host side command
Transmission system	Serial transmission (bit serial transmission)
Transmission code,	ASCII: 7-bit data, 1 start, 1 stop, even parity	Configured by user
configuration
Transmission code outgoing	Sent out from the lowest bit in character units
sequence
Error control	Vertical parity check, checksum, overrun check, framing check
Transmission unit	Message unit (variable length)
Maximum message length	503 bytes (including control characters)	1,024 bytes
	Note: 505 bytes when the station number is used.
Control procedure	H-series dedicated procedure (h-protocol)	Configured by user
	Standard protocol (transmission control procedure 1),
	Simplified protocol (transmission control procedure 2)
Interface	RS-422/485 (maximum cable length: 250 m)
Connector	CPU side: 15-pin D-sub
	Cable side: a cable equivalent to 17JE-23150-02(D8B) (DDK Co., Ltd.) is recommended (D-SUB
	fitting screw M3 ⋅ 0.5)

(1)Setting port 2

Port 2 is configured by special register WRF03D. The settings can be changed even when port 2 is communicating. The highest bit (b15) of WRF03D is setting bit.

If station number mode is used, make sure to set the station number from 0 to 31 in BCD code.

Value in WRF03D is saved in FLASH memory when writing flag (R7F6) is turned on. If saved in FLASH memory, it is not necessary to set again at the next power up.

(Example) Transmission control procedure 2, communication speed 19.2 kbps, and station number 28. Î WRF03D = HE228 After the setting is completed, WRF03D is changed to H6228. (b15 cleared)

Bit:

WRF03D: Initial value:

15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
a	b	c	0			d					e
0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

Figure 11.3 Special internal output for setting port 2

Field	Setting value	Content		Note
a	0	Setting completed		After the setting is completed, the
				system changes this bit to 0.
	1	Setting change request		Set this bit to 1 when changing the
				setting.
b	0	Transmission control procedure 1
	1	Transmission control procedure 2
c	0	Without station number
	1	With station number
d	0	Transmission speed	4800 bps	Setting of bits 8 to 12	H0000
	1		9600 bps		H0001
	2		19.2 kbps		H0010
	3		38.4 kbps		H0011
	Other than above		4800 bps
e	0 ~ 31	Station number *		Set by BCD.

*Communication speed of general purpose port is configured in TRNS/RECV command. Value in WRF03D is ignored.

11-3