The Speaker Company TTP 248M service manual Parallel Port Circuit, Vdd

TTP-248M Bar Code Printer

Service Manual

U19 is used for industrial long-distance asynchronous communication;U19 is optional.

3.13 Parallel Port Circuit

		PR8 10 K PR7 10 K	PR6	10 K	PR5
		R17			10 K
JP4	38
	37	10 K
19	1	/Write			PR22
20	2	D0
21	3	D1
22	4	D2
23	5	D3			PR23
24	6	D4
25	7	D5
26	8	D6
27	9	D7			PR24
28	10	In tr
29	11	/Wait
30	12	PE
31	13	SELECT			PR25
32	14	/DStrb
33	15	/AStrb
34	16	ERROR
35	17	/In it			R56
36	18
		VDD
		R19
CENTRONIC		10 K
GND DIGITAL GND

PC1

22 0p PC2

22 0p PC3

22 0p PC4

22 0p

C5

22 0p

U6A

74 HCT1 4

/Write/Writ e

10 0

1

2

U2/9 8

D0

U2/1 00

D1

U2/1 01

D2

U2/1 02

10 0

D3

U2/1 03

D4

U2/1 04

D5

U2/1 05

D6

U2/1 06

10 0

D7

U6F

U2/1 07

12

13

In tr

U2/1 10

/Wait

74 HCT1 4

U2/1 11

11

10

10 0

U6E

74 HCT1 4

/DStrb

U2/1 12

/AStrb

U2/1 13

10 0

/In it

U2/1 15

4

3

PE

PE

R18

6 U6C

U6B5

74 HCT1 4

10 K

SELECT

SELECT

VDD

U6D

74 HCT1 4

8

9

ERROR

ERROR

PR1

10 K

PR2

10 K PR3

10 K PR4

10 K

74 HCT1 4

Fig. 3.16 Parallel Port Circuit

Censorings port is SPP mode and one-way communication.

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