Timer board II JP: タイマーボードII（日本アセンブラ (JAC) C bus board for time measurement and control. User's manual issued in October 1986, According to the description of the programmer's manual etc., the push button for reaction loading Type switch box, voice key, photo sensor, proximity using ultrasonic wave Human / animal behavior measurement with switch, N88-BASIC / machine language program etc. It seems to be part of the time control part of the system but the details are unknown.In use User's manual and programmer's manual will be essential (You will also need the included software). Connectors for external connection are 8 mini plug jacks and 1 8-pin female round connector. There is one 8 series dip switch and 2 3 jumper switches on the board. Used element (1) Two i8253A (equivalent products) 　6 input points.An interrupt occurs independently of the external interrupt.Internal interrupt 　/ External interrupts can be determined by software.Stopwatch Combined Channel 　Supports 2 channels (4 channels with options included).Countable 　The maximum time is the basic clock x65535 ^ 2. (2) Time standard 8651B (8651A option) 　Original vibration 100 kHz (60 KHz).Frequency accuracy ± 5 ppm (25 ° C).The clock is 　Settings can be changed by program (1 to 1000 ms in basic software). (3) PPI i8255A-5 (equivalent product) 　Counter gate opening / closing (output): 6 bits 　Clock mode setting to timer (output): 6 bits 　Lead wire for external control (input / output): 4 bits × 2 (independently settable input / output) (4) Interruption 　Assembled by two i8259A on board and input to int 0 of PC-98. (5) Back connector 　One DIN terminal for interrupt switch inputs # 1 to 4 (one for DIN terminals # 5 to 8 is optional). 　Among them, # 2, # 3 (and optional # 6, # 7) are also used for stopwatch input. 　Mini plug jack for external input / output: 8 pieces (6) I / O port address 　EEh (output): 8651 B (reference clock) division ratio setting 　EEh (input): Read out the upper 7 bits of the address decoder (dip switch 　　　　　　　 Set by) 　xxD4h to xxD7h: 8259A x 2 (word accessible) 　xxD8h to xxDFh: 8253 x 2 (word accessible) 　xXD8h to xXDEh: 8255 (even addresses only.Byte access) 　However, x is a value set by the dip switch, and X is x + 1. ・ 8 series dip switches: Setting of upper 7 bits among 16 bits of address (Factory setting: All OFF) Dip 1 is NC. Assuming that ON = 0 and OFF = 1, for example, OFF-ON-ON-ON-OFF-ON-ON-OFF Is 0-0-0-1-0-0-1, and the upper address of the LSI group on the board is 12h. In the case of this example, the interrupt controller 8259A operates in 12D4h to 12D7h, 12D8h to 12DFh (note) timer 8253, 13D8h to 13DEh input / output port 8255A Each is selected.The setting status of this switch is to read port EEh You can know it by. Note: In the programmer's manual, it is 12D8h to 12D9h. * On most expansion boards, decode only the lower 8 bits of the I / O port address 　Not in.When used with such a board, bus conflict 　Be careful because it causes ・ Three jumper switches JP1, JP2: Setting of input / output direction of external input terminal JP1 is bit 0 to 3 (mini plug jacks 1 to 4), JP2 is bit 4 to 7 (5 to 8) Determine the direction.For both jumper switches, set the output with two G-side shorts. It becomes the setting of the input in the opposite side 2 short circuit.Do not use external input / output terminals In the case, set to G side (output side). Rear connector ・ Mini plug jack for input and output When viewing the board from the back side (card plastic side, opposite to the edge connector), 1, 2, 3, ... 7, 8 from the right.The signal is TTL level and positive logic.Input and output lines Twisted pair wire.When changing to negative logic, two 74LS243s beside JP1 and JP2 Replace with 74LS242. ・ 8 pin female round connector The connector pin number, 7 6 3 8 1 5 4 2 If you 　1 = switch 1 signal (negative logic) 　2 = Switch 2 signal (negative logic): Also used for stopwatch input 　3 = switch 3 signal (negative logic): same as above 　4 = switch 4 signal (negative logic) 　5 = + 5V 　6 = GND 　7 = Shield 　8 = NC Parallel back of CUT and silk-printed land by 8-pin female round connector The pattern and the through holes on both sides of the pattern are for the mini plug jacks for input and output. If you use an opportunity contact for the input signal, the CR integration circuit for chattering elimination is used. It is for attaching (pattern cut required).