Control Unit of CPLD Programmer
This is the control unit to write the data of the JED file in the CPLD device.
As for the circuit diagram, refer to "Circuit drawing of CPLD Programmer".
The main part of circuit is based on the information which the Xilinx Inc. makes open on the following site for the person who want to build own download cable.
JTAG Parallel Download Cable Schematic
Parallel port
The CPLD programmer is connected with the parallel port of the personal computer. A printer is generally connected with the parallel port.
The figure on the left shows the signal of each pin of the parallel port.
A pin numbering is written by the small character at the connector. Because the assignment position with number becomes opposite on the side of the male connector and the side of the female connector, make not make a mistake. The 1st pin is connected with the 1st pin of the opposing connector.
The 8, 11 and 12th pins are connected at the connector. These three pins seem to be the one to confirm whether or not a programmer is connected.
Bus buffer circuit
A bus buffer is put in the signal conductor of JTAG(TMS, TCK, TDI and TDO). 3 State buffer is used for buffer circuit. By this, the writing circuit to the CPLD device doesn't influence the parallel port of the personal computer. The buffer circuit works only when transferring data with the CPLD device. When not transferring data, the output of the buffer becomes high impedance and becomes the condition which was separated from the circuit. When the transfer of the data is done, the buffer becomes low impedance to the CPLD device and makes the writing of data possible.
When the C terminal is H level, output terminal (Y) becomes high impedance. In this condition, it becomes the same when a bus buffer isn't connected.
When the C terminal becomes an L level, the condition of input terminal (A) comes out to output terminal (Y).
Because there is a high impedance condition in addition to H level and L level, this buffer is called a 3 State buffer.
In the table, Z shows a high impedance condition.
Device switching circuit
A device is switched by the rotary switch. Either one device can be controlled.
Because it uses only any one generally, it is to be OK even if it doesn't switch. In the case, it is necessary to be careful when using.
In case of the PWB mode, the power supply to the CPLD device uses the outside power. It is possible to use the power of this equipment only in about 100 mA.
LED display
The green LED displays the situation of power (Vcc) and the TDI-signal makes a red LED light up at the time of the L level.
Because the red LED is during the blink while forwarding data, don't dissolve to switch off the power, to pull out a cable and to remove a device.
To make an influence over the TDI-signal little, the value of the resistor to be putting in the LED in series is big comparatively.
Power circuit
This power circuit makes the stable voltage(+5V) which the bus buffer and the CPLD device needs.
3 terminal regulator is used to get +5V output from +12V power in.
Control Unit
This unit is composed of the bus buffer circuit and the power circuit for the JTAG signal.
PLCC socket
The sockets for 44 pins and 84 pins are mounted on the unit. I want zero pressure type like the PIC programmer. However, it can not be realized by the structure of the socket.
To remove a device from the socket is a little complicated.
DSUB-25 connector ( Female )
This is the connector to connect the cable of the personal computer.
As for the connector of the cable which was used this time, the both edges were to do male connector being. Therefore, the connector of the female is used for the side of the programmer.
Cable for DSUB-25
This is the cable that the both edges had a male connector. The cable which all of the 25 pins are connected with should be used for this cable. When using a cable for the modem, it should use a straight cable. It is not a crossing cable.
Case
I used an aluminum case.
The size of the case has 100-mm width, 30-mm height, 140-mm depth.
Rotary switch
This switch is used for ON/OFF of the power and switching of 44 pins, 84 pins, the outside JTAG. The selection of either of 44 pins, 84 pins or the outside JTAG by this switch. A 6 circuit -4 contact type is used.
Knob
As the knob of the switch, the type for which the position of the switch is easy to see is used.
LED for the programming display
The green LED lights up when turned on. The white LED(The lighting-up color is red) blinks when writing data in the CPLD device.
Outside JTAG cable connector
This connector is used to connect with the CPLD device which is mounted on the printed board outside.
Connector of JTAG of the side of the printed board
This is the connector to mount on the printed board outside. A shape isn't decided. I used the connector which is as small as possible to make implementing space little.
Generally, I write data in CPLD using the programmer. So, I don't put a connector to the printed board outside.
Power connector
The inputting voltage of the unit is +12 V. The inner circuit works at +5 V using the regulator.
AC adapter
This device changes to DC 12V from AC 100V.
Front panel
The panel which was printed with the color printer is put to the surface of the programmer.
I put in printed paper with the acrylic board with 0.5-mm thickness.
Terminal
This is the terminal to confirm CPLD in the operation. All PLCC pins are connected with the terminal.
PLCC socket assembly
The sockets for 44 pins, 84 pins and for the outside JTAG are mounted on the universal printed board. The printed board which mounted sockets is put to the lid of the case. As for the position of the sockets, the operation of the screwdriver must be considered when removing a device.
Installation of the rotary switch
I considered the operability of the switch and I put the switch on the upper right of the case.
Installation of the printed board for the socket
As the procedure which is installed a printed board on the lid of the case, it puts marks to the position of the sockets and makes holes on the lid of the case using the handsaw and the files so on.
When attaching a device to the PLCC socket, power is gained to the printed board. To prevent from the damaging of a printed board by this power, I fixed on the position of the four corners of the socket with the case using the plate screw. The screws are hidden behind the panel.
Installation of the DSUB-25 connector
DSUB-25 connector is installed on the back of the equipment. The form of the connector isn't square. I made a hole which is smaller a little than the connector with the handsaw and shaved to the size of the connector with the file.
Installation of the control unit
This unit is installed in the position which doesn't touch a rotary switch.
Installation of the LED
It is installed in the position where the display is easy to see.
JTAG cable
This is the cable to write data in CPLD to have mounted on the printed board.
This is the control unit to write the data of the JED file in the CPLD device.
 |  Pattern drawing Parts explanation |
As for the circuit diagram, refer to "Circuit drawing of CPLD Programmer".
 |  |
JTAG Parallel Download Cable Schematic
Parallel portThe CPLD programmer is connected with the parallel port of the personal computer. A printer is generally connected with the parallel port.
The figure on the left shows the signal of each pin of the parallel port.
A pin numbering is written by the small character at the connector. Because the assignment position with number becomes opposite on the side of the male connector and the side of the female connector, make not make a mistake. The 1st pin is connected with the 1st pin of the opposing connector.
At the equipment this time, each pin is used as follows.
In the table above, the IN and OUT are the direction of the signal which was seen from the side of the personal computer.
It becomes contrary to the seeing from the side of the equipment.
| Pin # | Usual name | Name this time | Useage |
|---|---|---|---|
| 2 | PD0(I/O) | DIN(OUT) | Data signal output(TDI) |
| 3 | PD1(I/O) | CLK(OUT) | Clock signal output(TCK) |
| 4 | PD2(I/O) | TMS_IN(OUT) | Mode selection output(TMS) |
| 5 | PD3(I/O) | CTRL(OUT) | Output control signal |
| 6 | PD4(I/O) | PROG(OUT) | Input control signal |
| 8 | PD6(I/O) | D6(OUT) | Signal for condition detection? |
| 11 | BUSY(IN) | BUSY(IN) | Busy detection |
| 12 | PE(IN) | PE(IN) | Parity error detection |
| 13 | SLCT(IN) | DONE(IN) | Data signal input(TDO) |
| 15 | ERR#(IN) | VCC SENSE(IN) | Dvice status detection |
| 18-25 | GND | GND | Grounding |
In the table above, the IN and OUT are the direction of the signal which was seen from the side of the personal computer.
It becomes contrary to the seeing from the side of the equipment.
The 8, 11 and 12th pins are connected at the connector. These three pins seem to be the one to confirm whether or not a programmer is connected.
Bus buffer circuit
|
A bus buffer is put in the signal conductor of JTAG(TMS, TCK, TDI and TDO). 3 State buffer is used for buffer circuit. By this, the writing circuit to the CPLD device doesn't influence the parallel port of the personal computer. The buffer circuit works only when transferring data with the CPLD device. When not transferring data, the output of the buffer becomes high impedance and becomes the condition which was separated from the circuit. When the transfer of the data is done, the buffer becomes low impedance to the CPLD device and makes the writing of data possible.
When the C terminal is H level, output terminal (Y) becomes high impedance. In this condition, it becomes the same when a bus buffer isn't connected.
When the C terminal becomes an L level, the condition of input terminal (A) comes out to output terminal (Y).
Because there is a high impedance condition in addition to H level and L level, this buffer is called a 3 State buffer.
In the table, Z shows a high impedance condition.
Device switching circuitA device is switched by the rotary switch. Either one device can be controlled.
Because it uses only any one generally, it is to be OK even if it doesn't switch. In the case, it is necessary to be careful when using.
In case of the PWB mode, the power supply to the CPLD device uses the outside power. It is possible to use the power of this equipment only in about 100 mA.
LED displayThe green LED displays the situation of power (Vcc) and the TDI-signal makes a red LED light up at the time of the L level.
Because the red LED is during the blink while forwarding data, don't dissolve to switch off the power, to pull out a cable and to remove a device.
To make an influence over the TDI-signal little, the value of the resistor to be putting in the LED in series is big comparatively.
Power circuitThis power circuit makes the stable voltage(+5V) which the bus buffer and the CPLD device needs.
3 terminal regulator is used to get +5V output from +12V power in.
Control UnitThis unit is composed of the bus buffer circuit and the power circuit for the JTAG signal.
PLCC socketThe sockets for 44 pins and 84 pins are mounted on the unit. I want zero pressure type like the PIC programmer. However, it can not be realized by the structure of the socket.
To remove a device from the socket is a little complicated.
DSUB-25 connector ( Female )This is the connector to connect the cable of the personal computer.
As for the connector of the cable which was used this time, the both edges were to do male connector being. Therefore, the connector of the female is used for the side of the programmer.
Cable for DSUB-25This is the cable that the both edges had a male connector. The cable which all of the 25 pins are connected with should be used for this cable. When using a cable for the modem, it should use a straight cable. It is not a crossing cable.
CaseI used an aluminum case.
The size of the case has 100-mm width, 30-mm height, 140-mm depth.
Rotary switchThis switch is used for ON/OFF of the power and switching of 44 pins, 84 pins, the outside JTAG. The selection of either of 44 pins, 84 pins or the outside JTAG by this switch. A 6 circuit -4 contact type is used.
KnobAs the knob of the switch, the type for which the position of the switch is easy to see is used.
LED for the programming displayThe green LED lights up when turned on. The white LED(The lighting-up color is red) blinks when writing data in the CPLD device.
Outside JTAG cable connectorThis connector is used to connect with the CPLD device which is mounted on the printed board outside.
Connector of JTAG of the side of the printed boardThis is the connector to mount on the printed board outside. A shape isn't decided. I used the connector which is as small as possible to make implementing space little.
Generally, I write data in CPLD using the programmer. So, I don't put a connector to the printed board outside.
Power connectorThe inputting voltage of the unit is +12 V. The inner circuit works at +5 V using the regulator.
AC adapterThis device changes to DC 12V from AC 100V.
Front panelThe panel which was printed with the color printer is put to the surface of the programmer.
I put in printed paper with the acrylic board with 0.5-mm thickness.
TerminalThis is the terminal to confirm CPLD in the operation. All PLCC pins are connected with the terminal.
PLCC socket assemblyThe sockets for 44 pins, 84 pins and for the outside JTAG are mounted on the universal printed board. The printed board which mounted sockets is put to the lid of the case. As for the position of the sockets, the operation of the screwdriver must be considered when removing a device.
 |  |
Installation of the rotary switchI considered the operability of the switch and I put the switch on the upper right of the case.
Installation of the printed board for the socketAs the procedure which is installed a printed board on the lid of the case, it puts marks to the position of the sockets and makes holes on the lid of the case using the handsaw and the files so on.
When attaching a device to the PLCC socket, power is gained to the printed board. To prevent from the damaging of a printed board by this power, I fixed on the position of the four corners of the socket with the case using the plate screw. The screws are hidden behind the panel.
 |  |
Installation of the DSUB-25 connectorDSUB-25 connector is installed on the back of the equipment. The form of the connector isn't square. I made a hole which is smaller a little than the connector with the handsaw and shaved to the size of the connector with the file.
Installation of the control unitThis unit is installed in the position which doesn't touch a rotary switch.
Installation of the LEDIt is installed in the position where the display is easy to see.
JTAG cableThis is the cable to write data in CPLD to have mounted on the printed board.
文章评论（2条评论）
登录后参与讨论
EE直播间
更多
-
无线前沿新技术与测试技术峰会-线上直播 直播时间： 12月05日 09:30 -
首场直播发布： Keysight AP5000 系列新型高性价比模拟信号源 直播时间： 12月06日 10:00 -
全面掌握功率表应用及校准 直播时间： 12月10日 10:00 -
提升毫米波信号测试精度 直播时间： 12月18日 14:00
关闭
站长推荐
/2 
/2
-
返回顶部
-
用户519920 2009-8-31 10:22
用户149863 2008-11-28 15:09