Brother 1250, HL-1030, 1240 service manual Theory of Operation

			TABLE OF CONTENTS
	4.2	Load Paper Manually		2-10
	4.3	Two Side Printing (Manual Duplexing)		2-11
		4.3.1 To print on both sides of the paper from the paper cassette		2-11
		4.3.2 To print on both sides of the paper from the manual feed slot		2-12
5.	CONTROL PANEL OPERATION			2-13
	5.1	Ready (Paper) LED Indications		2-13
	5.2	Data (Toner) LED Indications		2-14
	5.3	Drum LED Indications		2-14
	5.4	Alarm LED Indications		2-14
	5.5	Control Panel Button Operations		2-15
	5.6	Other Control Features		2-15
		5.6.1	Sleep mode	2-15
		5.6.2	Test print mode	2-16
6. NETWORK BOARD OPERATION (FOR HL-1270N ONLY)				2-17
	6.1	Preparing the BR-net Board		2-17
		6.1.1	Connect the Ethernet cable	2-17
		6.1.2 Install the BRAdmin32: configuration utility (for Windows 95/98/NT 4.0 users only)		2-17
		6.1.3	Print configuration page	2-18
	6.2	Functions		2-18
		6.2.1	LED functions	2-18
		6.2.2	Factory default setting	2-18
CHAPTER 3 THEORY OF OPERATION				3-1
1.	ELECTRONICS			3-1
	1.1	General Block Diagram		3-1
	1.2	Main PCB Block Diagram		3-4
	1.3	Main PCB		3-7
		1.3.1	ASIC	3-7
		1.3.2	ROM	3-10
		1.3.3	Flash ROM	3-12
		1.3.4	DRAM	3-12
		1.3.5	Optional RAM	3-14
		1.3.6	Optional serial I/O	3-15
		1.3.7	PCI bus	3-15
		1.3.8	EEPROM	3-16
		1.3.9	Reset circuit	3-16
		1.3.10 Engine I/O		3-17
	1.4	Engine PCB		3-18
	1.5	BR-net PCB (for HL-1270 only)		3-18
	1.6	Power Supply		3-19
		1.6.1	Low-voltage Power Supply	3-19
		1.6.2	High-voltage Power Supply	3-20
2.	MECHANICS			3-21
	2.1	Overview of Printing Mechanism		3-21
	2.2	Paper Transfer		3-23
		2.2.1	Paper supply	3-23
		2.2.2	Paper registration	3-23

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