Processing box chip and signal demodulation method thereof

Abstract

The invention provides a processing box chip, comprising a contact set, a rectifying tank circuit, a demodulation circuit for demodulating a input signal, an micro control unit (MCU) and a modulation circuit for demodulating a output signal, wherein the touch set is connected with a printer, the rectifying tank circuit rectifies and filters the input signal, the demodulation circuit demodulates the input signal, and the modulation circuit modules an output signal; the demodulation circuit comprises diodes D4 and D5 and a resistance R3; the anodes of the diodes D4 and D5 are respectively connected with the contacts A and B of the contact set, the cathodes of the diodes D4 and D5 are connected with one end of the resistance R3 and are connected to the IO1 of the MCU, IO1 is the external interruption pin of the MCU, and the other end of the resistance R3 is earthed; two ends of the resistance R2 are respectively connected with the contact A of the contact set and the pin IO2 of the MCU, so that a clock signal is served as the synchronous clock for demodulating the signal and a synchronous signal for clearing an interruption mark. The invention also provides a signal demodulation method of the processing box chip, and the processing box chip adopted the invention has high reliability and good stability.

Description

technical field [0001] The invention relates to a chip and its demodulation method, in particular to a chip mounted on a processing box specially used to transmit information with a printer and a method for demodulating data signals by the processing box chip. Background technique [0002] The existing laser printer process box is equipped with a process box chip that can exchange information with the printer and has an information storage function. This chip enables the printer to read the information stored in the chip. For example, the printer can read from the process box chip. Take the type information corresponding to the processing cartridge for comparison and identification, and also write the relevant information reflecting the state of the processing cartridge into the processing cartridge chip; the printer can write the use history of the processing cartridge into the In the process cartridge chip, the manufacturer can read the information about the use history f...

AI Technical Summary

Problems solved by technology

[0003] As customers have higher requirements for printing quality, the requirements for the stable performance of the processing box chip are also gradually increasing. In addition, the speed requirements of the processing box chip are getting higher and higher, and the power consumption requirements are getting lower and lower. In order to limit the processing box chip The power consumption of the chip, the usual way is to reduce the power supplied by the printer or reduce the modulation duty cycle. Although the above method can reduce the power consumption of the chip, it will cause a large limit on the processing capacity of the MCU (microcontroller); moreover, At present, most processing box chips use direct IO operation to process data. When the modulation duty cycle is reduced and the signal period is very short, the MCU must have a high system clock speed to receive the modulation signal. It will lead to increased power consumption of the MCU and cause chip instability; figure 1 In a kind of existing process box chip circuit structure shown, the pin IO1 and IO2 of MCU directly receive the B signal and A signal that electric capacity C2 and C3 couple, when demodulating printer modulation signal, MCU is in pin IO2 ( A signal) is a falling edge, and read the level of IO1 (B signal) within time t, if the reading pin IO1 is low level, it will be demodulated to a bit 0 signal, if the reading pin IO1 is high level level is then demodulated to a bit 1 signal (see figure 2 )

Therefore, the speed requirements of the MCU are very high; if the duty cycle of the modulation of the A signal and the B signal is reduced and the signal period T is very short, such as figure 2 As shown, since the chip uses direct IO operations for data processing, the MCU must have a high system clock speed to receive the modulated signal, otherwise, data may be lost during the process of detecting data, resulting in improper operation of the chip. Stablize

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